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Bibliography on: Symbiosis

The Electronic Scholarly Publishing Project: Providing world-wide, free access to classic scientific papers and other scholarly materials, since 1993.


ESP: PubMed Auto Bibliography 27 May 2022 at 01:51 Created: 


Symbiosis refers to an interaction between two or more different organisms living in close physical association, typically to the advantage of both. Symbiotic relationships were once thought to be exceptional situations. Recent studies, however, have shown that every multicellular eukaryote exists in a tight symbiotic relationship with billions of microbes. The associated microbial ecosystems are referred to as microbiome and the combination of a multicellular organism and its microbiota has been described as a holobiont. It seems "we are all lichens now."

Created with PubMed® Query: symbiosis NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)


RevDate: 2022-05-26

Siden-Kiamos I, Koidou V, Livadaras I, et al (2022)

Dynamic interactions between the symbiont Candidatus Erwinia dacicola and its olive fruit fly host Bactrocera oleae.

Insect biochemistry and molecular biology pii:S0965-1748(22)00075-3 [Epub ahead of print].

The olive fruit fly, Bactrocera oleae, the most serious pest of olives, requires the endosymbiotic bacterium Candidatus Erwinia dacicola in order to complete its development in unripe green olives. Hence, a better understanding of the symbiosis of Ca. E. dacicola and its insect host may lead to new strategies for B. oleae control. The relative abundance of bacteria during the fly life cycle comparing black and green olives was estimated by real time quantitative PCR revealing significant fluctuations during development in black olives with a peak of the bacteria in the second instar larvae. By microscopy analysis of larvae, we show that the bacteria reside extracellularly in the gastric caeca. During the transition to late third instar larvae, the bacteria were discharged into the midgut concomitant with a change in caeca size and morphology due to the contraction of the muscles surrounding the caeca. A similar alteration was also observed in a laboratory strain devoid of bacteria. To further investigate the symbiotic interaction and the change in caeca morphology a comparative transcriptomics analysis was undertaken. Samples of dissected caeca from second and third instar larvae collected from the field as well as second instar larvae from a laboratory strain devoid of symbionts showed significant changes in transcript expression. This highlighted genes associated with the developmental changes revealed by the microscopic analysis as well as responses to microorganisms.

RevDate: 2022-05-26

Garetier M, Rousset J, Makki K, et al (2022)

Assessment and comparison of image quality between two real-time sequences for dynamic MRI of distal joints at 3.0 Tesla.

Acta radiologica (Stockholm, Sweden : 1987) [Epub ahead of print].

BACKGROUND: Real-time sequences allow functional evaluation of various joint structures during a continuous motion and help understand the pathomechanics of underlying musculoskeletal diseases.

PURPOSE: To assess and compare the image quality of the two most frequently used real-time sequences for joint dynamic magnetic resonance imaging (MRI), acquired during finger and ankle joint motion.

MATERIAL AND METHODS: A real-time dynamic acquisition protocol, including radiofrequency (RF)-spoiled and balanced steady-state free precession (bSSFP) sequences, optimized for temporal resolution with similar spatial resolution, was performed using a 3.0-T MRI scanner on 10 fingers and 12 ankles from healthy individuals during active motion. Image quality criteria were evaluated on each time frame and compared between these two sequences. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were determined and compared from regions of interest placed on cortical bone, tendon, fat, and muscle. Visualization of anatomical structures and overall image quality appreciation were rated by two radiologists using a 0-10 grading scale.

RESULTS: Mean CNR was significantly higher with bSSFP sequence compared to RF-spoiled sequence. The grading score was in the range of 5-9.3 and was significantly higher with RF-spoiled sequence for bone and joint evaluation and overall image appreciation on the two joints. The standard deviation for SNR, CNR, and grading score during motion was smaller with RF-spoiled sequence for both the joints. The inter-reader reliability was excellent (>0.75) for evaluating anatomical structures in both sequences.

CONCLUSION: A RF-spoiled real-time sequence is recommended for the in vivo clinical evaluation of distal joints on a 3.0-T MRI scanner.

RevDate: 2022-05-26

Jadhav S, Jadhav V, K Angadi (2022)

Berberine: Best Alternative Medicine Insight Abating Global Challenges for Treatment of MRSA Infections [Letter].

Infection and drug resistance, 15:2573-2574 pii:373391.

RevDate: 2022-05-26
CmpDate: 2022-05-26

Varas O, Pulgar J, Duarte C, et al (2022)

Parasitism by metacercariae modulates the morphological, organic and mechanical responses of the shell of an intertidal bivalve to environmental drivers.

The Science of the total environment, 830:154747.

Environmental variation alters biological interactions and their ecological and evolutionary consequences. In coastal systems, trematode parasites affect their hosts by disrupting their life-history traits. However, the effects of parasitism could be variable and dependent on the prevailing environmental conditions where the host-parasite interaction occurs. This study compared the effect of a trematode parasite in the family Renicolidae (metacercariae) on the body size and the shell organic and mechanical characteristics of the intertidal mussels Perumytilus purpuratus, inhabiting two environmentally contrasting localities in northern and central Chile (ca. 1600 km apart). Congruent with the environmental gradient along the Chilean coast, higher levels of temperature, salinity and pCO2, and a lower pH characterise the northern locality compared to that of central Chile. In the north, parasitised individuals showed lower body size and shell resistance than non-parasitised individuals, while in central Chile, the opposite pattern was observed. Protein level in the organic matter of the shell was lower in the parasitised hosts than in the non-parasitised ones regardless of the locality. However, an increase in polysaccharide levels was observed in the parasitised individuals from central Chile. These results evidence that body size and shell properties of P. purpuratus vary between local populations and that they respond differently when confronting the parasitism impacts. Considering that the parasite prevalence reaches around 50% in both populations, if parasitism is not included in the analysis, the true response of the host species would be masked by the effects of the parasite, skewing our understanding of how environmental variables will affect marine species. Considering parasitism and identifying its effects on host species faced with environmental drivers is essential to understand and accurately predict the ecological consequences of climate change.

RevDate: 2022-05-20
CmpDate: 2022-05-20

Mizumoto N, Bourguignon T, T Kanao (2022)

Termite nest evolution fostered social parasitism by termitophilous rove beetles.

Evolution; international journal of organic evolution, 76(5):1064-1072.

Colonies of social insects contain large amounts of resources often exploited by specialized social parasites. Although some termite species host numerous parasitic arthropod species, called termitophiles, others host none. The reason for this large variability remains unknown. Here, we report that the evolution of termitophily in rove beetles is linked to termite nesting strategies. We compared one-piece nesters, whose entire colony life is completed within a single wood piece, to foraging species, which exploit multiple physically separated food sources. Our epidemiological model predicts that characteristics related to foraging (e.g., extended colony longevity and frequent interactions with other colonies) increase the probability of parasitism by termitophiles. We tested our prediction using literature data. We found that foraging species are more likely to host termitophilous rove beetles than one-piece nesters: 99.6% of known termitophilous species were associated with foraging termites, whereas 0.4% were associated with one-piece nesters. Notably, the few one-piece nesting species hosting termitophiles were those having foraging potential and access to soil. Our phylogenetic analyses confirmed that termitophily primarily evolved with foraging termites. These results highlight that the evolution of complex termite societies fostered social parasitism, explaining why some species have more social parasites than others.

RevDate: 2022-05-25

Han Y, Lou X, Zhang W, et al (2022)

Arbuscular Mycorrhizal Fungi Enhanced Drought Resistance of Populus cathayana by Regulating the 14-3-3 Family Protein Genes.

Microbiology spectrum [Epub ahead of print].

Plants can improve their resistance to a variety of stresses by forming mutualistic relationships with arbuscular mycorrhizal fungi (AMF). The 14-3-3 protein is a major regulator of the plant stress response. However, the regulation mechanism of 14-3-3 family protein genes (14-3-3s) of mycorrhizal plants coping with stress during AMF symbiosis remains unclear. Here, we analyzed the physiological changes and 14-3-3 expression profiles of Populus cathayana inoculated with AMF under different water conditions. The results showed that good colonization and symbiotic relationships with plants were formed under all water conditions (63.00% to 83.67%). Photosynthesis, peroxidase (POD) activity, and Mg and Ca content were significantly affected by drought and AMF. In addition, thirteen 14-3-3 protein genes (PcGRF1-PcGRF13) were identified by quantitative real-time PCR (qRT-PCR), of which the expression levels of PcGRF10 and PcGRF11 induced by AMF were significantly positively correlated with superoxide dismutase (SOD), POD, and sugar content, indicating that the 14-3-3s of mycorrhizal symbiotic plants may respond to drought through antioxidant and osmotic regulation. This is the first study on 14-3-3s in the symbiosis system of forest arbor plants and AMF, and it may help to further study the effects of 14-3-3s during AMF symbiosis on stresses and provide new ideas for improving mycorrhizal seedling cultivation under stress. IMPORTANCE The 14-3-3 protein may regulate many biochemical and physiological processes under abiotic stress. Studies have shown that the 14-3-3 protein gene of AMF is not only upregulated under drought stress, but also enhances the regulation of AMF on plant drought tolerance by regulating plant signal pathways and drought response genes; however, knowledge about the biological relevance of these interactions remains limited and controversial. The precise functions of Populus cathayana 14-3-3s under drought stress remain poorly resolved and the mechanisms of action of these genes in mycorrhizae-induced drought stress are still unknown. Thus, studying the drought-resistance mechanism of the AMF symbiotic plant 14-3-3 gene is of special significance to improving the drought tolerance of the plant. Further systematic study is needed to probe the mechanism by which AMF regulates different 14-3-3 genes and their subsequent physiological effects on drought.

RevDate: 2022-05-25

Robes JMD, Altamia MA, Murdock EG, et al (2022)

A Conserved Biosynthetic Gene Cluster Is Regulated by Quorum Sensing in a Shipworm Symbiont.

Applied and environmental microbiology [Epub ahead of print].

Bacterial symbionts often provide critical functions for their hosts. For example, wood-boring bivalves called shipworms rely on cellulolytic endosymbionts for wood digestion. However, how the relationship between shipworms and their bacterial symbionts is formed and maintained remains unknown. Quorum sensing (QS) often plays an important role in regulating symbiotic relationships. We identified and characterized a QS system found in Teredinibacter sp. strain 2052S, a gill isolate of the wood-boring shipworm Bactronophorus cf. thoracites. We determined that 2052S produces the signal N-decanoyl-l-homoserine lactone (C10-HSL) and that this signal controls the activation of a biosynthetic gene cluster colocated in the symbiont genome that is conserved among all symbiotic Teredinibacter isolates. We subsequently identified extracellular metabolites associated with the QS regulon, including ones linked to the conserved biosynthetic gene cluster, using mass spectrometry-based molecular networking. Our results demonstrate that QS plays an important role in regulating secondary metabolism in this shipworm symbiont. This information provides a step toward deciphering the molecular details of the relationship between these symbionts and their hosts. Furthermore, because shipworm symbionts harbor vast yet underexplored biosynthetic potential, understanding how their secondary metabolism is regulated may aid future drug discovery efforts using these organisms. IMPORTANCE Bacteria play important roles as symbionts in animals ranging from invertebrates to humans. Despite this recognized importance, much is still unknown about the molecular details of how these relationships are formed and maintained. One of the proposed roles of shipworm symbionts is the production of bioactive secondary metabolites due to the immense biosynthetic potential found in shipworm symbiont genomes. Here, we report that a shipworm symbiont uses quorum sensing to coordinate activation of its extracellular secondary metabolism, including the transcriptional activation of a biosynthetic gene cluster that is conserved among many shipworm symbionts. This work is a first step toward linking quorum sensing, secondary metabolism, and symbiosis in wood-boring shipworms.

RevDate: 2022-05-25

Luu TB, Ourth A, Pouzet C, et al (2022)

A newly-evolved chimeric lysin motif receptor-like kinase in Medicago truncatula spp. tricycla R108 extends its Rhizobia symbiotic partnership.

The New phytologist [Epub ahead of print].

Rhizobial lipochitooligosaccharidic Nod factors (NFs), specified by nod genes, are the primary determinants of host specificity in the legume-Rhizobia symbiosis. We examined the nodulation ability of Medicago truncatula cv Jemalong A17 and M. truncatula ssp. tricycla R108 with the Sinorhizobium meliloti nodF/nodL mutant, which produces modified NFs. We then applied genetic and functional approaches to study the genetic basis and mechanism of nodulation of R108 by this mutant. We show that the nodF/nodL mutant can nodulate R108 but not A17. Using genomics and reverse genetics, we identified a newly-evolved, chimeric LysM receptor-like kinase gene in R108, LYK2bis, which is responsible for the phenotype and can allow A17 to gain nodulation with the nodF/nodL mutant. We found that LYK2bis is involved in nodulation by mutants producing non-O-acetylated NFs and interacts with the key receptor protein NFP. Many, but not all natural S. meliloti and S. medicae strains tested require LYK2bis for efficient nodulation of R108. Our findings reveal that a newly-evolved gene in R108, LYK2bis, extends nodulation specificity to mutants producing non-O-acetylated NFs and is important for nodulation by many natural Sinorhizobia. Evolution of this gene may present an adaptive advantage to allow nodulation by a greater variety of strains.

RevDate: 2022-05-24

Okuda S, Hirose Y, Takihara H, et al (2022)

Unveiling microbiome profiles in human inner body fluids and tumor tissues with pancreatic or biliary tract cancer.

Scientific reports, 12(1):8766.

With the discovery of bacterial symbiosis in the tissues of various cancers, the study of the tumor microbiome is attracting a great deal of attention. Anatomically, since the gastrointestinal tract, liver, and pancreas form a continuous ductal structure, the microbiomes in the digestive juices of these organs may influence each other. Here, we report a series of microbiome data in tumor-associated tissues such as tumor, non-tumor, and lymph nodes, and body fluids such as saliva, gastric juice, pancreatic juice, bile, and feces of patients with pancreatic or biliary tract cancers. The results show that the microbiome of tumor-associated tissues has a very similar bacterial composition, but that in body fluids has different bacterial composition which varies by location, where some bacteria localize to specific body fluids. Surprisingly, Akkermansia was only detected in the bile of patients with biliary tract cancer and its presence was significantly associated with the performance of external biliary drainage (P = 0.041). Furthermore, we found that tumor-associated tissues and body fluids in deep inner body are mostly inhabited by unidentified and uncharacterized bacteria, suggesting that such bacteria may be potential targets for precision therapy in the future.

RevDate: 2022-05-24

Paliya S, Mandpe A, Bhisikar D, et al (2022)

Polybrominated diphenyl ethers (PBDEs) in Indian wastewater treatment plant: Occurrence, mass flow and removal.

Chemosphere pii:S0045-6535(22)01548-X [Epub ahead of print].

Polybrominated diphenyl ethers (PBDEs) are categorized as a group of brominated flame retardants that cause hazardous health impacts but are still being used consistently worldwide. The studies on their occurrence and fate in wastewater treatment plants are scarce, and considering the Indian scenario, no study has been reported till date in this context. Therefore, in the present study, PBDE congeners of primary concern were investigated first time to assess the existence, dissemination and fate of PBDEs in the municipal wastewater treatment plant (MWTP) located in Nagpur city, Maharashtra, India. BDE 209 and 47 were detected as the predominant PBDE contaminants in all the analysed samples. The concentration of PBDEs was primarily found in the particulate phase of wastewater. According to mass loading analysis, 1297 mg/day concentration of PBDEs is disposed of at landfill sites in the form of sludge, while 77.46 mg/day is released via final effluent. The present investigation is the first of its kind of study conducted to evaluate the PBDE contamination in Indian MWTP, which reveals the presence of high PBDE concentration in Indian municipal sewage. The findings of the current study exhibit the need for appropriate action toward the sound surveillance of PBDEs in the Indian context.

RevDate: 2022-05-24

Margarita V, Bailey NP, Rappelli P, et al (2022)

Two Different Species of Mycoplasma Endosymbionts Can Influence Trichomonas vaginalis Pathophysiology.

mBio [Epub ahead of print].

Trichomonas vaginalis can host the endosymbiont Mycoplasma hominis, an opportunistic pathogenic bacterium capable of modulating T. vaginalis pathobiology. Recently, a new noncultivable mycoplasma, "Candidatus Mycoplasma girerdii," has been shown to be closely associated with women affected by trichomoniasis, suggesting a biological association. Although several features of "Ca. M. girerdii" have been investigated through genomic analysis, the nature of the potential T. vaginalis-"Ca. M. girerdii" consortium and its impact on the biology and pathogenesis of both microorganisms have not yet been explored. Here, we investigate the association between "Ca. M. girerdii" and T. vaginalis isolated from patients affected by trichomoniasis, demonstrating their intracellular localization. By using an in vitro model system based on single- and double-Mycoplasma infection of Mycoplasma-free isogenic T. vaginalis, we investigated the ability of the protist to establish a relationship with the bacteria and impact T. vaginalis growth. Our data indicate likely competition between M. hominis and "Ca. M. girerdii" while infecting trichomonad cells. Comparative dual-transcriptomics data showed major shifts in parasite gene expression in response to the presence of Mycoplasma, including genes associated with energy metabolism and pathogenesis. Consistent with the transcriptomics data, both parasite-mediated hemolysis and binding to host epithelial cells were significantly upregulated in the presence of either Mycoplasma species. Taken together, these results support a model in which this microbial association could modulate the virulence of T. vaginalis. IMPORTANCE T. vaginalis and M. hominis form a unique case of endosymbiosis that modulates the parasite's pathobiology. Recently, a new nonculturable mycoplasma species ("Candidatus Mycoplasma girerdii") has been described as closely associated with the protozoon. Here, we report the characterization of this endosymbiotic relationship. Clinical isolates of the parasite demonstrate that mycoplasmas are common among trichomoniasis patients. The relationships are studied by devising an in vitro system of single and/or double infections in isogenic protozoan recipients. Comparative growth experiments and transcriptomics data demonstrate that the composition of different microbial consortia influences the growth of the parasite and significantly modulates its transcriptomic profile, including metabolic enzymes and virulence genes such as adhesins and pore-forming proteins. The data on modulation from RNA sequencing (RNA-Seq) correlated closely with those of the cytopathic effect and adhesion to human target cells. We propose the hypothesis that the presence and the quantitative ratios of endosymbionts may contribute to modulating protozoan virulence. Our data highlight the importance of considering pathogenic entities as microbial ecosystems, reinforcing the importance of the development of integrated diagnostic and therapeutic strategies.

RevDate: 2022-05-24
CmpDate: 2022-05-24

Hemmerle L, Maier BA, Bortfeld-Miller M, et al (2022)

Dynamic character displacement among a pair of bacterial phyllosphere commensals in situ.

Nature communications, 13(1):2836.

Differences between species promote stable coexistence in a resource-limited environment. These differences can result from interspecies competition leading to character shifts, a process referred to as character displacement. While character displacement is often interpreted as a consequence of genetically fixed trait differences between species, it can also be mediated by phenotypic plasticity in response to the presence of another species. Here, we test whether phenotypic plasticity leads to a shift in proteome allocation during co-occurrence of two bacterial species from the abundant, leaf-colonizing families Sphingomonadaceae and Rhizobiaceae in their natural habitat. Upon mono-colonizing of the phyllosphere, both species exhibit specific and shared protein functions indicating a niche overlap. During co-colonization, quantitative differences in the protein repertoire of both bacterial populations occur as a result of bacterial coexistence in planta. Specifically, the Sphingomonas strain produces enzymes for the metabolization of xylan, while the Rhizobium strain reprograms its metabolism to beta-oxidation of fatty acids fueled via the glyoxylate cycle and adapts its biotin acquisition. We demonstrate the conditional relevance of cross-species facilitation by mutagenesis leading to loss of fitness in competition in planta. Our results show that dynamic character displacement and niche facilitation mediated by phenotypic plasticity can contribute to species coexistence.

RevDate: 2022-05-18
CmpDate: 2022-05-18

Gall BG, Stokes AN, Brodie ED, et al (2022)

Tetrodotoxin levels in lab-reared Rough-Skinned Newts (Taricha granulosa) after 3 years and comparison to wild-caught juveniles.

Toxicon : official journal of the International Society on Toxinology, 213:7-12.

The origin and biogenesis of tetrodotoxin (TTX) is one of the most interesting and perplexing questions remaining for TTX researchers. Newts can possess extreme quantities of TTX and are one of the most well-studied of all TTX-bearing organisms, yet seemingly conflicting results between studies on closely related species continues to generate debate. In this study, eggs from 12 female newts (Taricha granulosa) were reared in captivity and the metamorphosed juveniles were fed a TTX-free diet for 3 years. Using a non-lethal sampling technique, we collected skin samples from each individual each year. Wild-caught juveniles from the same population were also sampled for TTX. In lab-reared juveniles, mass increased rapidly, and after only 2 years individuals approached adult body mass. TTX levels increased slowly during the first two years and then jumped considerably in year three when fed a diet free of TTX. However, wild-caught juvenile newts of unknown age were more toxic than their lab-reared counterparts. These results, coupled with additional data on the long-term production and synthesis of TTX in adult newts suggest that TTX is unlikely to come through dietary acquisition, but rather newts may be able to synthesize their own toxin or acquire it from symbiotic bacteria.

RevDate: 2022-05-24
CmpDate: 2022-05-24

Jhu MY, NR Sinha (2022)

Parasitic Plants: An Overview of Mechanisms by Which Plants Perceive and Respond to Parasites.

Annual review of plant biology, 73:433-455.

In contrast to most autotrophic plants, which produce carbohydrates from carbon dioxide using photosynthesis, parasitic plants obtain water and nutrients by parasitizing host plants. Many important crop plants are infested by these heterotrophic plants, leading to severe agricultural loss and reduced food security. Understanding how host plants perceive and resist parasitic plants provides insight into underlying defense mechanisms and the potential for agricultural applications. In this review, we offer a comprehensive overview of the current understanding of host perception of parasitic plants and the pre-attachment and post-attachment defense responses mounted by the host. Since most current research overlooks the role of organ specificity in resistance responses, we also summarize the current understanding and cases of cross-organ parasitism, which indicates nonconventional haustorial connections on other host organs, for example, when stem parasitic plants form haustoria on their host roots. Understanding how different tissue types respond to parasitic plants could provide the potential for developing a universal resistance mechanism in crops against both root and stem parasitic plants.

RevDate: 2022-05-24
CmpDate: 2022-05-24

Semchenko M, Barry KE, de Vries FT, et al (2022)

Deciphering the role of specialist and generalist plant-microbial interactions as drivers of plant-soil feedback.

The New phytologist, 234(6):1929-1944.

Feedback between plants and soil microbial communities can be a powerful driver of vegetation dynamics. Plants elicit changes in the soil microbiome that either promote or suppress conspecifics at the same location, thereby regulating population density-dependence and species co-existence. Such effects are often attributed to the accumulation of host-specific antagonistic or beneficial microbiota in the rhizosphere. However, the identity and host-specificity of the microbial taxa involved are rarely empirically assessed. Here we review the evidence for host-specificity in plant-associated microbes and propose that specific plant-soil feedbacks can also be driven by generalists. We outline the potential mechanisms by which generalist microbial pathogens, mutualists and decomposers can generate differential effects on plant hosts and synthesize existing evidence to predict these effects as a function of plant investments into defence, microbial mutualists and dispersal. Importantly, the capacity of generalist microbiota to drive plant-soil feedbacks depends not only on the traits of individual plants but also on the phylogenetic and functional diversity of plant communities. Identifying factors that promote specialization or generalism in plant-microbial interactions and thereby modulate the impact of microbiota on plant performance will advance our understanding of the mechanisms underlying plant-soil feedback and the ways it contributes to plant co-existence.

RevDate: 2022-05-19
CmpDate: 2022-05-19

Heckley AM, de Lira JJPR, Hendry AP, et al (2022)

How might Gyrodactylus parasitism modify trade-offs between female preference and susceptibility of males to predation in Trinidadian guppies?.

International journal for parasitology, 52(7):459-467.

A number of examples exist of trade-offs between mating success and survival; that is, success in one fitness component comes at the cost of success in the other fitness component. However, these expected trade-offs are - perhaps even more commonly - not observed. One explanation for this apparent paradox of missing trade-offs could be that the other factors generating fitness variation across individuals confound or obscure the expected trade-off. These confounding effects could arise in two general ways: (i) the additional source of variation could positively (or negatively) influence both fitness components ("shared confounder" hypothesis), or (ii) the additional source of variation could influence only one fitness component ("non-shared confounder" hypothesis). We tested whether parasitism by Gyrodactylus spp. could be a confounder of trade-offs between female preference and susceptibility to predation for male Trinidadian guppies (Poecilia reticulata). As in previous work, we did not find the expected trade-off; that is, the males preferred by females were not more likely to be eaten by predators. Because half of the experimental males were infected by Gyrodactylus in a paired design, we were able to show that females discriminated against infected males, but that infected males were not more susceptible to predation. Our results thus provide support for the non-shared confounder hypothesis. That is, by negatively affecting one fitness component (female choice) but not the other (susceptibility to predation), parasitism by Gyrodactylus could obscure the expected trade-off between female preference and susceptibility to predation.

RevDate: 2022-05-23

Snelders NC, Rovenich H, BPHJ Thomma (2022)

Microbiota manipulation through the secretion of effector proteins is fundamental to the wealth of lifestyles in the fungal kingdom.

FEMS microbiology reviews pii:6590816 [Epub ahead of print].

Fungi are well-known decomposers of organic matter that thrive in virtually any environment on earth where they encounter wealths of other microbes. Some fungi evolved symbiotic lifestyles, including pathogens and mutualists, that have mostly been studied in binary interactions with their hosts. However, we now appreciate that such interactions are greatly influenced by the ecological context in which they take place. While establishing their symbioses, fungi not only interact with their hosts, but also with the host-associated microbiota. Thus, they target the host and its associated microbiota as a single holobiont. Recent studies have shown that fungal pathogens manipulate the host microbiota by means of secreted effector proteins with selective antimicrobial activity to stimulate disease development. In this review we discuss the ecological contexts in which such effector-mediated microbiota manipulation is relevant for the fungal lifestyle and argue that this is not only relevant for pathogens of plants and animals, but beneficial in virtually any niche where fungi occur. Moreover, we reason that effector-mediated microbiota manipulation likely evolved already in fungal ancestors that encountered microbial competition long before symbiosis with land plants and mammalian animals evolved. Thus, we claim that effector-mediated microbiota manipulation is fundamental to fungal biology.

RevDate: 2022-05-23

Dominelli N, Platz F, R Heermann (2022)

The Insect Pathogen Photorhabdus luminescens Protects Plants from Phytopathogenic Fusarium graminearum via Chitin Degradation.

Applied and environmental microbiology [Epub ahead of print].

Phytopathogens represent a large agricultural challenge. The use of chemical pesticides is harmful to the environment, animals, and humans. Therefore, new sustainable and biological alternatives are urgently needed. The insect-pathogenic bacterium Photorhabdus luminescens, already used in combination with entomopathogenic nematodes (EPNs) as a biocontrol agent, is characterized by two different phenotypic cell forms, called primary (1°) and secondary (2°). The 1° cells are symbiotic with EPNs and are used for biocontrol, and the 2° cells are unable to undergo symbiosis with EPNs, remain in the soil after insect infection, and specifically interact with plant roots. A previous RNA sequencing (RNAseq) analysis showed that genes encoding the exochitinase Chi2A and chitin binding protein (CBP) are highly upregulated in 2° cells exposed to plant root exudates. Here, we investigate Chi2A and CBP functions and demonstrate that both are necessary for P. luminescens 2° cells to inhibit the growth of the phytopathogenic fungus Fusarium graminearum. We provide evidence that Chi2A digests chitin and thereby inhibits fungal growth. Furthermore, we show that 2° cells specifically colonize fungal hyphae as one of the first mechanisms to protect plants from fungal phytopathogens. Finally, soil pot bioassays proved plant protection from F. graminearum by 2° cells, where Chi2A and CPB were essential for this process. This work gives molecular insights into the new applicability of P. luminescens as a plant-growth-promoting and plant-protecting organism in agriculture. IMPORTANCE The enteric enterobacterium Photorhabdus luminescens is already being used as a bioinsecticide since it is highly pathogenic toward a broad range of insects. However, the bacteria exist in two phenotypically different cell types, called 1° and 2° cells. Whereas only 1° cells are symbiotic with their nematode partner to infect insects, 2° cells were shown to remain in the soil after an insect infection cycle. It was demonstrated that 2° cells specifically interact with plant roots. Here, we show that the bacteria are beneficial for the plants by protecting them from phytopathogenic fungi. Specific colonization of the fungus mycelium as well as chitin-degrading activity mediated by the chitin binding protein (CBP) and the chitinase Chi2A are essential for this process. Our data give evidence for the novel future applicability of P. luminescens as a plant-growth-promoting organism and biopesticide.

RevDate: 2022-05-23

Ma Z, Zhao X, He A, et al (2022)

Mycorrhizal symbiosis reprograms ion fluxes and fatty acid metabolism in wild jujube during salt stress.

Plant physiology pii:6590662 [Epub ahead of print].

Chinese jujube (Ziziphus jujuba) is an important fruit tree in China, and soil salinity is the main constraint affecting jujube production. It is unclear how arbuscular mycorrhizal (AM) symbiosis supports jujube adaptation to salt stress. Herein, we performed comparative physiological, ion flux, fatty acid (FA) metabolomic, and transcriptomic analyses to examine the mechanism of AM jujube responding to salt stress. AM seedlings showed better performance during salt stress. AM symbiosis altered phytohormonal levels: IAA and ABA contents were significantly increased in AM roots and reduced by salt stress. Mycorrhizal colonization enhanced root H+ efflux and K+ influx, while inducing expression of plasma membrane-type ATPase 7 (ZjAHA7) and high-affinity K+ transporter 2 (ZjHAK2) in roots. High K+/Na+ homeostasis was maintained throughout salt exposure. FA content was elevated in AM leaves as well as roots, especially for palmitic acid, oleic acid, trans oleic acid, and linoleic acid, and similar effects were also observed in AM poplar (P. alba × P. glandulosa cv. 84K) and Medicago truncatula, indicating AM symbiosis elevating FA levels could be a conserved physiological effect. Gene co-expression network analyses uncovered a core gene set including 267 genes in roots associated with AM symbiosis and conserved transcriptional responses, e.g., FA metabolism, phytohormone signal transduction, SNARE interaction in vesicular transport, and biotin metabolism. In contrast to widely up-regulated genes related to FA metabolism in AM roots, limited genes were affected in leaves. We propose a model of AM symbiosis-linked reprogramming of FA metabolism and provide a comprehensive insight into AM symbiosis with a woody species adaptation to salt stress.

RevDate: 2022-05-23

Gore MN, AR Patwardhan (2022)

Disparities in the Cost of Living Adjusted Earnings of Female Sex Workers in India, Thailand, and the USA: A Need to Create an Equitable Economic Survival of Female Sex Workers.

Journal of primary care & community health, 13:21501319221101857.

Financial necessity and desperation is the primary reason for females to enter into sex work. The health and well-being of female sex workers (FSWs) depend on the balance between their earnings and the cost of living in their local environment. Therefore it would be of value to examine the comparative cost of living adjusted earnings of FSWs in different countries to gauge equity or its absence in their financial state. Data about per client per encounter earnings for FSWs in Pune, India was taken from primary research conducted by the first author. Equivalent secondary data was acquired for the US and Thailand from an online literature review. Earnings after converting to US dollar values were adjusted against the cost of living in the respective environments of the FSWs and then compared. An FSW in India, (Pune) earned on the average US $4.40 after adjusting for the cost of living locally, while in Thailand (Bangkok) the equivalent earning was US $18.77 and in the US (Washington DC region) it was $101.79. These results suggest that an FSW in the US earns 23 times more, and a Thai FSW earns 4 times more than an FSW in India. There are numerous variables that affect the earnings of an FSW and the limited defined scope of this paper based on available data does not permit detailed analyses of causal or intermediate influencing factors. Nonetheless, it can be said with reasonable confidence that much needs to be done and can be done to mitigate the earning disparity, particularly in an emerging economy like India as shown in this small study, and that can perhaps be done best under the umbrella domain of a "harm reduction approach."

RevDate: 2022-05-23

Das D, Sarkar A, A Debroy (2022)

Impact of COVID-19 on changing consumer behaviour: Lessons from an emerging economy.

International journal of consumer studies, 46(3):692-715.

The present study investigates the impact of COVID-19 on Consumers' changing way of life and buying behaviour based on their socio-economic backgrounds. A questionnaire survey was carried out to understand the impact of COVID-19 on consumers' affordability, lifestyle, and health awareness and how these effects influenced their buying behaviour. A total of 425 usable responses were analysed using the structural equation modelling considering Consumers' socio-economic background as exogenous variables and Consumers' changing way of life and Adaptation in consumers' buying behaviour as endogenous variables. The study reveals that COVID-19 has affected the consumers in the unorganised sectors more than others and induced an increase in the demand for affordable substitutes for daily necessities. The demand for wellness and entertainment products is found to depend upon the occupation and family earning status of consumers which is jointly mediated by affordability and lifestyle changes. Further, the findings show that the demand for health and hygiene products depends on the current employment status and family earning status of consumers which is jointly mediated by affordability and awareness towards health and hygiene. The model developed in the present study allows the decision-makers to identify which segments of the population with certain socio-economic backgrounds could be targeted for wellness products and which ones could be targeted for health and hygiene products. In addition, the model provides rich insights to the managers as to what kind of product substitution would be viable in the market during the pandemic.

RevDate: 2022-05-23

Vishnu RA, Alamelu S, Arun KV, et al (2022)

Comparative evaluation of subgingival microbiome in healthy periodontium and gingivitis using next-generation sequencing technology: A case-control study.

Journal of Indian Society of Periodontology, 26(3):224-229.

Background: Human dental plaque is a complex microbial community containing millions of species. Gingivitis is a dysregulated immune-inflammatory response induced by dysbiotic plaque biofilm that interrupts symbiosis. The emergence of next-generation sequencing with 16S rRNA gene has greatly contributed in understanding the complexity of microbiota. However, studies focusing on microbiome in gingivitis are limited. The whole bacterial community is important in causing periodontal disease than a small number of periodontal pathogens. In this study, we attempted to profile the subgingival microbiome from individuals with healthy gingiva and in patients with gingivitis using next-generation sequencing technology.

Materials and Methods: Subgingival plaque samples from 15 healthy periodontium (Group I) and 15 gingivitis (Group II) were collected and 16s rRNA sequencing was done in Illumina Solexa Sequencer. Data analysis using 16s metagenomics tool from BaseSpace onsite operational taxonomic units was assigned to each sequence using HOMD database. Individual variation in the microbiome of the subgingival samples between the two groups was also evaluated.

Results: The comparison of top 20 species between Group I and Group II revealed no significant species group between them. Synergistetes was absent in Group I samples but found in Group II. At the genus level, HACEK group species were found in both the groups, while Dialister and Aneroglobus were found abundantly in the Group II.

Conclusion: The presence of unique genera and species seen in Group II samples could point toward a dysbiotic shift that could be taking place in the subgingival environment leading to gingivitis.

RevDate: 2022-05-23

Mishra S, Shaw K, Mishra D, et al (2022)

Improving the Accuracy of Ensemble Machine Learning Classification Models Using a Novel Bit-Fusion Algorithm for Healthcare AI Systems.

Frontiers in public health, 10:858282.

Healthcare AI systems exclusively employ classification models for disease detection. However, with the recent research advances into this arena, it has been observed that single classification models have achieved limited accuracy in some cases. Employing fusion of multiple classifiers outputs into a single classification framework has been instrumental in achieving greater accuracy and performing automated big data analysis. The article proposes a bit fusion ensemble algorithm that minimizes the classification error rate and has been tested on various datasets. Five diversified base classifiers k- nearest neighbor (KNN), Support Vector Machine (SVM), Multi-Layer Perceptron (MLP), Decision Tree (D.T.), and Naïve Bayesian Classifier (N.B.), are used in the implementation model. Bit fusion algorithm works on the individual input from the classifiers. Decision vectors of the base classifier are weighted transformed into binary bits by comparing with high-reliability threshold parameters. The output of each base classifier is considered as soft class vectors (CV). These vectors are weighted, transformed and compared with a high threshold value of initialized δ = 0.9 for reliability. Binary patterns are extracted, and the model is trained and tested again. The standard fusion approach and proposed bit fusion algorithm have been compared by average error rate. The error rate of the Bit-fusion algorithm has been observed with the values 5.97, 12.6, 4.64, 0, 0, 27.28 for Leukemia, Breast cancer, Lung Cancer, Hepatitis, Lymphoma, Embryonal Tumors, respectively. The model is trained and tested over datasets from UCI, UEA, and UCR repositories as well which also have shown reduction in the error rates.

RevDate: 2022-05-23

Ren CG, Kong CC, Liu ZY, et al (2022)

A Perspective on Developing a Plant 'Holobiont' for Future Saline Agriculture.

Frontiers in microbiology, 13:763014.

Soil salinity adversely affects plant growth and has become a major limiting factor for agricultural development worldwide. There is a continuing demand for sustainable technology innovation in saline agriculture. Among various bio-techniques being used to reduce the salinity hazard, symbiotic microorganisms such as rhizobia and arbuscular mycorrhizal (AM) fungi have proved to be efficient. These symbiotic associations each deploy an array of well-tuned mechanisms to provide salinity tolerance for the plant. In this review, we first comprehensively cover major research advances in symbiont-induced salinity tolerance in plants. Second, we describe the common signaling process used by legumes to control symbiosis establishment with rhizobia and AM fungi. Multi-omics technologies have enabled us to identify and characterize more genes involved in symbiosis, and eventually, map out the key signaling pathways. These developments have laid the foundation for technological innovations that use symbiotic microorganisms to improve crop salt tolerance on a larger scale. Thus, with the aim of better utilizing symbiotic microorganisms in saline agriculture, we propose the possibility of developing non-legume 'holobionts' by taking advantage of newly developed genome editing technology. This will open a new avenue for capitalizing on symbiotic microorganisms to enhance plant saline tolerance for increased sustainability and yields in saline agriculture.

RevDate: 2022-05-23

Talwar N, NM Holden (2022)

The limitations of bioeconomy LCA studies for understanding the transition to sustainable bioeconomy.

The international journal of life cycle assessment, 27(5):680-703.

Purpose: Transition to bioeconomy requires all actors and stakeholders to measure the impact of systems that use bioresources and technologies to provision society. There are however some challenges with integrating LCA into business development and management, which have important implications for bioeconomy. There have been many LCA studies published in the twenty-first century, but the question must be answered: how useful are these LCA studies to help understand and manage transition to sustainable bioeconomy?

Method: This research used a structured literature review to identify 83 bioeconomy LCA studies published from January 2006 to June 2021 (excluding bioenergy). The studies were analysed for compliance with the ISO 14044 standard, with specific reference to the goal, commissioning perspective, system boundary, function and functional unit, impact methods and categories.

Results and discussions: It was found that more than 85% of the studies reviewed failed to present the required goal statement and a description of the function of the system. Nearly 13% of the studies did not define the system boundary, and only 17% included a full life cycle including raw material extraction, production, use and end-of-life stages. The majority of the LCA studies surveyed from 2006 to 2021 were either (i) not in compliance with the ISO standards or (ii) space and style limitations of the publication process prevented competent practitioners from properly conveying their work. This suggests that the value and integrity of the literature are undermined by not rigorously addressing the first and most important stage of an LCA study.

Conclusion: When interpreting the results, a major shortcoming noted was that most studies did not consider the industrial symbiosis needed between feedstock, technology, primary products, side streams, downstream valorisation and long-term circularity in order to properly understand the transition pathways required. Bioeconomy technologies were imagined as displacers for feedstocks and processes to adapt business as usual, rather than as transformers of the system to a sustainable footing.

Recommendation: If LCA studies are going to provide meaningful information for actors and stakeholders to assess whether a system will be able to operate sustainably, studies should include a full, integrated system, standards should be adhered to and approaches should perhaps go beyond mere eco-efficiency, or doing less harm, as these are not necessarily indicative of sustainability. Historical bioeconomy LCA studies do not provide great insight into the transition to sustainable bioeconomy.

Supplementary information: The online version contains supplementary material available at 10.1007/s11367-022-02053-w.

RevDate: 2022-05-23

Khatri R, Pant SR, Sharma K, et al (2022)

Glycine max Homologs of DOESN'T MAKE INFECTIONS 1, 2, and 3 Function to Impair Heterodera glycines Parasitism While Also Regulating Mitogen Activated Protein Kinase Expression.

Frontiers in plant science, 13:842597.

Glycine max root cells developing into syncytia through the parasitic activities of the pathogenic nematode Heterodera glycines underwent isolation by laser microdissection (LM). Microarray analyses have identified the expression of a G. max DOESN'T MAKE INFECTIONS3 (DMI3) homolog in syncytia undergoing parasitism but during a defense response. DMI3 encodes part of the common symbiosis pathway (CSP) involving DMI1, DMI2, and other CSP genes. The identified DMI gene expression, and symbiosis role, suggests the possible existence of commonalities between symbiosis and defense. G. max has 3 DMI1, 12 DMI2, and 2 DMI3 paralogs. LM-assisted gene expression experiments of isolated syncytia under further examination here show G. max DMI1-3, DMI2-7, and DMI3-2 expression occurring during the defense response in the H. glycines-resistant genotypes G.max [Peking/PI548402] and G.max [PI88788] indicating a broad and consistent level of expression of the genes. Transgenic overexpression (OE) of G. max DMI1-3, DMI2-7, and DMI3-2 impairs H. glycines parasitism. RNA interference (RNAi) of G. max DMI1-3, DMI2-7, and DMI3-2 increases H. glycines parasitism. The combined opposite outcomes reveal a defense function for these genes. Prior functional transgenic analyses of the 32-member G. max mitogen activated protein kinase (MAPK) gene family has determined that 9 of them act in the defense response to H. glycines parasitism, referred to as defense MAPKs. RNA-seq analyses of root RNA isolated from the 9 G. max defense MAPKs undergoing OE or RNAi reveal they alter the relative transcript abundances (RTAs) of specific DMI1, DMI2, and DMI3 paralogs. In contrast, transgenically-manipulated DMI1-3, DMI2-7, and DMI3-2 expression influences MAPK3-1 and MAPK3-2 RTAs under certain circumstances. The results show G. max homologs of the CSP, and defense pathway are linked, apparently involving co-regulated gene expression.

RevDate: 2022-05-23
CmpDate: 2022-05-23

Verhoeve VI, Fauntleroy TD, Risteen RG, et al (2022)

Cryptic Genes for Interbacterial Antagonism Distinguish Rickettsia Species Infecting Blacklegged Ticks From Other Rickettsia Pathogens.

Frontiers in cellular and infection microbiology, 12:880813.

Background: The genus Rickettsia (Alphaproteobacteria: Rickettsiales) encompasses numerous obligate intracellular species with predominantly ciliate and arthropod hosts. Notable species are pathogens transmitted to mammals by blood-feeding arthropods. Mammalian pathogenicity evolved from basal, non-pathogenic host-associations; however, some non-pathogens are closely related to pathogens. One such species, Rickettsia buchneri, is prevalent in the blacklegged tick, Ixodes scapularis. While I. scapularis transmits several pathogens to humans, it does not transmit Rickettsia pathogens. We hypothesize that R. buchneri established a mutualism with I. scapularis, blocking tick superinfection with Rickettsia pathogens.

Methods: To improve estimates for assessing R. buchneri infection frequency in blacklegged tick populations, we used comparative genomics to identify an R. buchneri gene (REIS_1424) not present in other Rickettsia species present throughout the I. scapularis geographic range. Bioinformatic and phylogenomics approaches were employed to propose a function for the hypothetical protein (263 aa) encoded by REIS_1424.

Results: REIS_1424 has few analogs in other Rickettsiales genomes and greatest similarity to non-Proteobacteria proteins. This cohort of proteins varies greatly in size and domain composition, possessing characteristics of Recombination hotspot (Rhs) and contact dependent growth inhibition (CDI) toxins, with similarity limited to proximal C-termini (~145 aa). This domain was named CDI-like/Rhs-like C-terminal toxin (CRCT). As such proteins are often found as toxin-antidote (TA) modules, we interrogated REIS_1423 (151 aa) as a putative antidote. Indeed, REIS_1423 is similar to proteins encoded upstream of CRCT domain-containing proteins. Accordingly, we named these proteins CDI-like/Rhs-like C-terminal toxin antidotes (CRCA). R. buchneri expressed both REIS_1423 and REIS_1424 in tick cell culture, and PCR assays showed specificity for R. buchneri over other rickettsiae and utility for positive detection in three tick populations. Finally, phylogenomics analyses uncovered divergent CRCT/CRCA modules in varying states of conservation; however, only R. buchneri and related Tamurae/Ixodes Group rickettsiae carry complete TA modules.

Conclusion: We hypothesize that Rickettsia CRCT/CRCA modules circulate in the Rickettsia mobile gene pool, arming rickettsiae for battle over arthropod colonization. While its functional significance remains to be tested, R. buchneri CRCT/CRCA serves as a marker to positively identify infection and begin deciphering the role this endosymbiont plays in the biology of the blacklegged tick.

RevDate: 2022-05-21

Zarka J, De Wint FC, De Bruyn L, et al (2022)

Dissecting the costs of a facultative symbiosis in an isopod living with ants.

Oecologia [Epub ahead of print].

The balance between costs and benefits is expected to drive associations between species. While these balances are well understood for strict associations, we have no insights to which extent they determine facultative associations between species. Here, we quantified the costs of living in a facultative association, by studying the effects of red wood ants on the facultatively associated isopod Porcellio scaber. Porcellio scaber frequently occurred in and near hostile red wood ant nests and might outnumber obligate nest associates. The facultative association involved different costs for the isopod. We found that the density of the isopod decreases near the nest with higher ant traffic. Individuals in and near the nest were smaller than individuals further away from the nest. Smaller individuals were also found at sites with higher ant traffic. A higher proportion of wounded individuals was found closer to the nest and with higher ant traffic. We recorded pregnant females and juveniles in the nest suggesting that the life cycle can be completed inside the nests. Lab experiments showed that females died sooner and invested less in reproduction in presence of red wood ants. Porcellio scaber rarely provoked an aggression response, but large numbers were carried as prey to the nest. These preyed isopods were mainly dried out corpses. Our results showed that the ant association incurred several costs for a facultative associate. Consequently, red wood ant nests and their surrounding territory act as an alternative habitat where demographic costs are offset by a stable resource provisioning and protection.

RevDate: 2022-05-21

Boubakri H, Najjar E, Jihnaoui N, et al (2022)

Genome-wide identification, characterization and expression analysis of glutaredoxin gene family (Grxs) in Phaseolus vulgaris.

Gene pii:S0378-1119(22)00410-3 [Epub ahead of print].

Glutaredoxins (Grxs) are ubiquitous oxidoreductase proteins implicated in development and abiotic stress response mainly through maintaining redox homoeostasis. Here, we conducted the first systematic analysis of the Grx gene family (PvGrx) in the most popular legume Phaseolus vulgaris (common bean). A total of 50 PvGrx genes were identified, and divided into four classes (CC-type, CGFS-type, CPYC-type and Grl-type) based on the phylogenetic analysis. The different classes have different introns-exons structures and conserved motifs, indicating functional divergence in the PvGrx family. Both tandem and segmental duplications were found to be involved in the expansion of PvGrx family that underwent a purifying selection by excluding the deleterious loss-of-function mutations. Cis-acting regulatory elements and gene ontology analyses predicted their role of distinctive members in abiotic stress response and hormonal signalling. RNA-seq based expression analysis revealed their differential expression pattern during plant development. On the other hand, RT q-PCR analysis revealed that target PvGrx isoforms were associated with nodule organogenesis and symbiosis based on their expression profiles. In addition, a battery of PvGrx candidates were markedly upregulated by different abiotic stressors suggesting their broad spectrum of functions. These findings serve as a reference for functional analysis and genetic improvement in P. vulgaris and related legume species.

RevDate: 2022-05-21

Nisar A, Ajabia DK, Agrawal SB, et al (2022)

Mechanistic insight into differential interactions of iron oxide nanoparticles with native, glycated albumin and their effect on erythrocytes parameters.

International journal of biological macromolecules pii:S0141-8130(22)01080-7 [Epub ahead of print].

Nanoparticles and protein bioconjugates have been studied for multiple biomedical applications. We sought to investigate the interaction and structural modifications of bovine serum albumin (BSA) with iron oxide nanoparticles (IONPs). The IONPs were green synthesized using E. crassipes aqueous leaf extract following characterization using transmission electron microscopy, energy dispersive X-ray analysis and X-Ray Diffraction. Two different concentrations of native/glycated albumin (0.5 and 1.5 mg/ml) with IONPs were allowed to interact for 1 h at 37 °C. Glycation markers, protein modification markers, cellular antioxidant, and hemolysis studies showed structural modifications and conformational changes in albumin due to the presence of IONPs. UV-Visible absorbance resulted in hyperchromic and bathochromic effects of IONPs-BSA conjugates. Fluorescence measurements of tyrosine, tryptophan, advanced glycated end products, and ANS binding assay were promising and quenching effects proved IONPs-BSA conjugate formation. In FTIR of BSA-IONPs, transmittance was increased in amide A and B bands while decreased in amide I and II bands. In summary, native PAGE, HPLC, and FTIR analysis displayed a differential behaviour of IONPs with native and glycated BSA. These results provided an understanding of the interaction and structural modifications of glycated and native BSA which may provide fundamental repercussions in future studies.

RevDate: 2022-05-21

Watts-Williams SJ (2022)

Track and trace: how soil labelling techniques have revealed the secrets of resource transport in the arbuscular mycorrhizal symbiosis.

Mycorrhiza [Epub ahead of print].

Arbuscular mycorrhizal (AM) fungi colonise plant roots, and by doing so forge the 'mycorrhizal uptake pathway(s)' (MUP) that provide passageways for the trade of resources across a specialised membrane at the plant-fungus interface. The transport of nutrients such as phosphorus (P), nitrogen and zinc from the fungus, and carbon from the plant, via the MUP have mostly been quantified using stable or radioactive isotope labelling of soil in a specialised hyphae-only compartment. Recent advances in the study of AM fungi have used tracing studies to better understand how the AM association will function in a changing climate, the extent to which the MUP can contribute to P uptake by important crops, and how AM fungi trade resources in interaction with plants, other AM fungi, and friend and foe in the soil microbiome. The existing work together with well-designed future experiments will provide a valuable assessment of the potential for AM fungi to play a role in the sustainability of managed and natural systems in a changing climate.

RevDate: 2022-05-20

Quach QN, Gardner DR, Clay K, et al (2022)

Phylogenetic Patterns of Swainsonine Presence in Morning Glories.

Frontiers in microbiology, 13:871148.

Endosymbionts play important roles in the life cycles of many macro-organisms. The indolizidine alkaloid swainsonine is produced by heritable fungi that occurs in diverse plant families, such as locoweeds (Fabaceae) and morning glories (Convolvulaceae) plus two species of Malvaceae. Swainsonine is known for its toxic effects on livestock following the ingestion of locoweeds and the potential for pharmaceutical applications. We sampled and tested herbarium seed samples (n = 983) from 244 morning glory species for the presence of swainsonine and built a phylogeny based on available internal transcribed spacer (ITS) sequences of the sampled species. We show that swainsonine occurs only in a single morning glory clade and host species are established on multiple continents. Our results further indicate that this symbiosis developed ∼5 mya and that swainsonine-positive species have larger seeds than their uninfected conspecifics.

RevDate: 2022-05-19

Unzueta-Martínez A, Scanes E, Parker LM, et al (2022)

Microbiomes of the Sydney Rock Oyster are acquired through both vertical and horizontal transmission.

Animal microbiome, 4(1):32.

BACKGROUND: The term holobiont is widely accepted to describe animal hosts and their associated microorganisms. The genomes of all that the holobiont encompasses, are termed the hologenome and it has been proposed as a unit of selection in evolution. To demonstrate that natural selection acts on the hologenome, a significant portion of the associated microbial genomes should be transferred between generations. Using the Sydney Rock Oyster (Saccostrea glomerata) as a model, we tested if the microbes of this broadcast spawning species could be passed down to the next generation by conducting single parent crosses and tracking the microbiome from parent to offspring and throughout early larval stages using 16S rRNA gene amplicon sequencing. From each cross, we sampled adult tissues (mantle, gill, stomach, gonad, eggs or sperm), larvae (D-veliger, umbo, eyed pediveliger, and spat), and the surrounding environment (water and algae feed) for microbial community analysis.

RESULTS: We found that each larval stage has a distinct microbiome that is partially influenced by their parental microbiome, particularly the maternal egg microbiome. We also demonstrate the presence of core microbes that are consistent across all families, persist throughout early life stages (from eggs to spat), and are not detected in the microbiomes of the surrounding environment. In addition to the core microbiomes that span all life cycle stages, there is also evidence of environmentally acquired microbial communities, with earlier larval stages (D-veliger and umbo), more influenced by seawater microbiomes, and later larval stages (eyed pediveliger and spat) dominated by microbial members that are specific to oysters and not detected in the surrounding environment.

CONCLUSION: Our study characterized the succession of oyster larvae microbiomes from gametes to spat and tracked selected members that persisted across multiple life stages. Overall our findings suggest that both horizontal and vertical transmission routes are possible for the complex microbial communities associated with a broadcast spawning marine invertebrate. We demonstrate that not all members of oyster-associated microbiomes are governed by the same ecological dynamics, which is critical for determining what constitutes a hologenome.

RevDate: 2022-05-19

Drury C, Bean NK, Harris CI, et al (2022)

Intrapopulation adaptive variance supports thermal tolerance in a reef-building coral.

Communications biology, 5(1):486.

Coral holobionts are multi-species assemblages, which adds significant complexity to genotype-phenotype connections underlying ecologically important traits like coral bleaching. Small scale heterogeneity in bleaching is ubiquitous in the absence of strong environmental gradients, which provides adaptive variance needed for the long-term persistence of coral reefs. We used RAD-seq, qPCR and LC-MS/MS metabolomics to characterize host genomic variation, symbiont community and biochemical correlates in two bleaching phenotypes of the vertically transmitting coral Montipora capitata. Phenotype was driven by symbiosis state and host genetic variance. We documented 5 gene ontologies that were significantly associated with both the binary bleaching phenotype and symbiont composition, representing functions that confer a phenotype via host-symbiont interactions. We bred these corals and show that symbiont communities were broadly conserved in bulk-crosses, resulting in significantly higher survivorship under temperature stress in juveniles, but not larvae, from tolerant parents. Using a select and re-sequence approach, we document numerous gene ontologies selected by heat stress, some of which (cell signaling, antioxidant activity, pH regulation) have unique selection dynamics in larvae from thermally tolerant parents. These data show that vertically transmitting corals may have an adaptive advantage under climate change if host and symbiont variance interact to influence bleaching phenotype.

RevDate: 2022-05-20
CmpDate: 2022-05-20

Passarge A, Doehlemann G, JC Misas Villamil (2022)

Detection of Apoplastic Protease Inhibitors Using Convolution Activity-Based Protein Profiling.

Methods in molecular biology (Clifton, N.J.), 2447:95-104.

Activity-based protein profiling (ABPP) is a powerful tool in biological chemistry to monitor protein activity using chemical probes that bind covalently and irreversible to active site of enzymes such as proteases. To date, there are three different ways to experimentally use ABPP: comparative, competitive, and convolution ABPP. Here we use and describe the convolution ABPP approach, a method used to detect changes in protease inhibitor abundance in different proteomes. We have applied this method to monitor the activity of Lolium perenne apoplastic cysteine proteases during the interaction with the fungal endophyte Epichloë festucae. We describe the method to isolate apoplastic fluids from infected and uninfected L. perenne ryegrass leaves and the protocol to perform a convolution ABPP experiment. Furthermore, we report how to quantify and analyze fluorescent gels obtained from the ABPP labeling.

RevDate: 2022-05-18
CmpDate: 2022-05-18

Sarkar I, Sen G, Bhattacharyya S, et al (2022)

Inter-cluster competition and resource partitioning may govern the ecology of Frankia.

Archives of microbiology, 204(6):326.

Microbes live in a complex communal ecosystem. The structural complexity of microbial community reflects diversity, functionality, as well as habitat type. Delineation of ecologically important microbial populations along with exploration of their roles in environmental adaptation or host-microbe interaction has a crucial role in modern microbiology. In this scenario, reverse ecology (the use of genomics to study ecology) plays a pivotal role. Since the co-existence of two different genera in one small niche should maintain a strict direct interaction, it will be interesting to utilize the concept of reverse ecology in this scenario. Here, we exploited an 'R' package, the RevEcoR, to resolve the issue of co-existing microbes which are proven to be a crucial tool for identifying the nature of their relationship (competition or complementation) persisting among them. Our target organism here is Frankia, a nitrogen-fixing actinobacterium popular for its genetic and host-specific nature. According to their plant host, Frankia has already been sub-divided into four clusters C-I, C-II, C-III, and C-IV. Our results revealed a strong competing nature of CI Frankia. Among the clusters of Frankia studied, the competition index between C-I and C-III was the largest. The other interesting result was the co-occurrence of C-II and C-IV groups. It was revealed that these two groups follow the theory of resource partitioning in their lifestyle. Metabolic analysis along with their differential transporter machinery validated our hypothesis of resource partitioning among C-II and C-IV groups.

RevDate: 2022-05-20
CmpDate: 2022-05-20

Smith TE, Li Y, Perreau J, et al (2022)

Elucidation of host and symbiont contributions to peptidoglycan metabolism based on comparative genomics of eight aphid subfamilies and their Buchnera.

PLoS genetics, 18(5):e1010195.

Pea aphids (Acyrthosiphon pisum) are insects containing genes of bacterial origin with putative functions in peptidoglycan (PGN) metabolism. Of these, rlpA1-5, amiD, and ldcA are highly expressed in bacteriocytes, specialized aphid cells that harbor the obligate bacterial symbiont Buchnera aphidicola, required for amino acid supplementation of the host's nutrient-poor diet. Despite genome reduction associated with endosymbiosis, pea aphid Buchnera retains genes for the synthesis of PGN while Buchnera of many other aphid species partially or completely lack these genes. To explore the evolution of aphid horizontally-transferred genes (HTGs) and to elucidate how host and symbiont genes contribute to PGN production, we sequenced genomes from four deeply branching lineages, such that paired aphid and Buchnera genomes are now available for 17 species representing eight subfamilies. We identified all host and symbiont genes putatively involved in PGN metabolism. Phylogenetic analyses indicate that each HTG family was present in the aphid shared ancestor, but that each underwent a unique pattern of gene loss or duplication in descendant lineages. While four aphid rlpA gene subfamilies show no relation to symbiont PGN gene repertoire, the loss of aphid amiD and ldcA HTGs coincides with the loss of symbiont PGN metabolism genes. In particular, the coincident loss of host amiD and symbiont murCEF in tribe Aphidini, in contrast to tribe Macrosiphini, suggests either 1) functional linkage between these host and symbiont genes, or 2) Aphidini has lost functional PGN synthesis and other retained PGN pathway genes are non-functional. To test these hypotheses experimentally, we used cell-wall labeling methods involving a d-alanine probe and found that both Macrosiphini and Aphidini retain Buchnera PGN synthesis. Our results imply that compensatory adaptations can preserve PGN synthesis despite the loss of some genes considered essential for this pathway, highlighting the importance of the cell wall in these symbioses.

RevDate: 2022-05-19

Rosani U (2022)

Tracing RNA viruses associated with Nudibranchia gastropods.

PeerJ, 10:e13410 pii:13410.

Background: Nudibranchia is an under-studied taxonomic group of gastropods, including more than 3,000 species with colourful and extravagant body shapes and peculiar predatory and defensive strategies. Although symbiosis with bacteria has been reported, no data are available for the nudibranch microbiome nor regarding viruses possibly associated with these geographically widespread species.

Methods: Based on 47 available RNA sequencing datasets including more than two billion reads of 35 nudibranch species, a meta-transcriptome assembly was constructed. Taxonomic searches with DIAMOND, RNA-dependent-RNA-polymerase identification with palmscan and viral hallmark genes identification by VirSorter2 in combination with CheckV were applied to identify genuine viral genomes, which were then annotated using CAT.

Results: A total of 20 viral genomes were identified as bona fide viruses, among 552 putative viral contigs resembling both RNA viruses of the Negarnaviricota, Pisuviricota, Kitrinoviricota phyla and actively transcribing DNA viruses of the Cossaviricota and Nucleocytoviricota phyla. The 20 commonly identified viruses showed similarity with RNA viruses identified in other RNA-seq experiments and can be putatively associated with bacteria, plant and arthropod hosts by co-occurence analysis. The RNA samples having the highest viral abundances showed a heterogenous and mostly sample-specific distribution of the identified viruses, suggesting that nudibranchs possess diversified and mostly unknown viral communities.

RevDate: 2022-05-19

Chetta P, G Zadra (2021)

Metabolic reprogramming as an emerging mechanism of resistance to endocrine therapies in prostate cancer.

Cancer drug resistance (Alhambra, Calif.), 4(1):143-162.

Prostate cancer (PCa) is the second leading cause of cancer-related death in the US. Androgen receptor (AR) signaling is the driver of both PCa development and progression and, thus, the major target of current in-use therapies. However, despite the survival benefit of second-generation inhibitors of AR signaling in the metastatic setting, resistance mechanisms inevitably occur. Thus, novel strategies are required to circumvent resistance occurrence and thereby to improve PCa survival. Among the key cellular processes that are regulated by androgens, metabolic reprogramming stands out because of its intricate links with cancer cell biology. In this review, we discuss how cancer metabolism and lipid metabolism in particular are regulated by androgens and contribute to the acquisition of resistance to endocrine therapy. We describe the interplay between genetic alterations, metabolic vulnerabilities and castration resistance. Since PCa cells adapt their metabolism to excess nutrient supply to promote cancer progression, we review our current knowledge on the association between diet/obesity and resistance to anti-androgen therapies. We briefly describe the metabolic symbiosis between PCa cells and tumor microenvironment and how this crosstalk might contribute to PCa progression. We discuss how tackling PCa metabolic vulnerabilities represents a potential approach of synthetic lethality to endocrine therapies. Finally, we describe how the continuous advances in analytical technologies and metabolic imaging have led to the identification of potential new prognostic and predictive biomarkers, and non-invasive approaches to monitor therapy response.

RevDate: 2022-05-17

Kawarai S, Taira K, Shimono A, et al (2022)

Author Correction: Seasonal and geographical differences in the ruminal microbial and chloroplast composition of sika deer (Cervus nippon) in Japan.

Scientific reports, 12(1):8219 pii:10.1038/s41598-022-12520-x.

RevDate: 2022-05-19
CmpDate: 2022-05-19

Yoshikawa A, Izumi T, Moritaki T, et al (2022)

Carcinoecium-Forming Sea Anemone Stylobates calcifer sp. nov. (Cnidaria, Actiniaria, Actiniidae) from the Japanese Deep-Sea Floor: A Taxonomical Description with Its Ecological Observations.

The Biological bulletin, 242(2):127-152.

AbstractHere we describe Stylobates calcifer sp. nov. (Cnidaria, Actiniaria, Actiniidae), a new carcinoecium-forming sea anemone from the deep-sea floor of Japan. Stylobates produces a carcinoecium that thinly covers the snail shells inhabited by host hermit crabs Pagurodofleinia doederleini. The new species is distinct from other species by the shape of the marginal sphincter muscle, the distribution of cnidae, the direction of the oral disk, and host association. The species' novelty is supported by the data of its mitochondrial genes 12S, 16S, and COIII and nuclear genes 18S and 28S. Also, we conducted behavioral observation of this new species, focusing on the feeding behavior and interaction with the specific host hermit crab. Our observations suggest that this sea anemone potentially feeds on the suspended particulate organic matter from the water column or the food residuals of hermit crabs. When the host's shell changed, intensive manipulation for transference of S. calcifer sp. nov. was recorded. However, although the hermit crab detached and transferred the sea anemone to the new shell after shell change, the sea anemone did not exhibit active or cooperative participation. Our data suggest that the sea anemone may not produce a carcinoecium synchronously to its host's growth, contrary to the anecdotal assumption about carcinoecium-forming sea anemones. Conversely, the host hermit crab's growth may not depend entirely on the carcinoecium produced by the sea anemone. This study is perhaps the first observation of the behavioral interaction of the rarely studied carcinoecium-forming mutualism in the deep sea.

RevDate: 2022-05-18

Busby PE, Newcombe G, Neat AS, et al (2022)

Facilitating Reforestation Through the Plant Microbiome: Perspectives from the Phyllosphere.

Annual review of phytopathology [Epub ahead of print].

Tree planting and natural regeneration contribute to the ongoing effort to restore Earth's forests. Our review addresses how the plant microbiome can enhance the survival of planted and naturally regenerating seedlings and serve in long-term forest carbon capture and the conservation of biodiversity. We focus on fungal leaf endophytes, ubiquitous defensive symbionts that protect against pathogens. We first show that fungal and oomycetous pathogen richness varies greatly for tree species native to the United States (n = 0-876 known pathogens per US tree species), with nearly half of tree species either without pathogens in these major groups or with unknown pathogens. Endophytes are insurance against the poorly known and changing threat of tree pathogens. Next, we reviewed studies of plant-phyllosphere feedback, but knowledge gaps prevented us from evaluating whether adding conspecific leaf litter to planted seedlings promotes defensive symbiosis, analogous to adding soil to promote positive feedback. Finally, we discuss research priorities for integrating the plant microbiome into efforts to expand Earth's forests. Expected final online publication date for the Annual Review of Phytopathology, Volume 60 is August 2022. Please see for revised estimates.

RevDate: 2022-05-18

Shao TY, Kakade P, Witchley JN, et al (2022)

Candida albicans oscillating UME6 expression during intestinal colonization primes systemic Th17 protective immunity.

Cell reports, 39(7):110837.

Systemic immunity is stringently regulated by commensal intestinal microbes, including the pathobiont Candida albicans. This fungus utilizes various transcriptional and morphological programs for host adaptation, but how this heterogeneity affects immunogenicity remains uncertain. We show that UME6, a transcriptional regulator of filamentation, is essential for intestinal C. albicans-primed systemic Th17 immunity. UME6 deletion and constitutive overexpression strains are non-immunogenic during commensal colonization, whereas immunogenicity is restored by C. albicans undergoing oscillating UME6 expression linked with β-glucan and mannan production. In turn, intestinal reconstitution with these fungal cell wall components restores protective Th17 immunity to mice colonized with UME6-locked variants. These fungal cell wall ligands and commensal C. albicans stimulate Th17 immunity through multiple host pattern recognition receptors, including Toll-like receptor 2 (TLR2), TLR4, Dectin-1, and Dectin-2, which work synergistically for colonization-induced protection. Thus, dynamic gene expression fluctuations by C. albicans during symbiotic colonization are essential for priming host immunity against disseminated infection.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Chen Y, Pan T, Chai G, et al (2022)

Complete genome of Mycetocola spongiae MSC19T isolated from deep-sea sponge Cacospongia mycofijiensis indicates the adaptation to deep-sea environment and sponge-microbe symbioses.

Marine genomics, 63:100955.

Genome of Mycetocola spongiae MSC19T, a novel marine sponge-associated Actinobacteria isolated from the Mariana Trench sponge Cacospongia mycofijiensis, was sequenced. The genome has one circular chromosome of 3,196,754 bp, with an average GC content of 66.43 mol%, and 2887 coding sequences. Gene annotation shows that M. spongiae MSC19T possesses series of genes related to adaptation to deep-sea environmental stresses including cold shock, heat shock, osmotic stress and oxidative stress. Genes encoding for heavy metal resistance, multidrug resistance and multiple natural product biosynthesis which are crucial for survival in the extreme environment are also detected in the genome. The potentials to synthesize kinds of vitamins and eukaryotic-like proteins indicates the possible nutrient exchange and mutual recognization between M. spongiae MSC19T and its sponge host. The genome provides insights into the stress resistance and ecological fitness of bacterial symbionts in the deep-sea sponge holobionts.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Monroy-Morales E, Dávila-Delgado R, Ayala-Guzmán E, et al (2022)

Visualization of the Crossroads between a Nascent Infection Thread and the First Cell Division Event in Phaseolus vulgaris Nodulation.

International journal of molecular sciences, 23(9):.

The development of a symbiotic nitrogen-fixing nodule in legumes involves infection and organogenesis. Infection begins when rhizobia enter a root hair through an inward structure, the infection thread (IT), which guides the bacteria towards the cortical tissue. Concurrently, organogenesis takes place by inducing cortical cell division (CCD) at the infection site. Genetic analysis showed that both events are well-coordinated; however, the dynamics connecting them remain to be elucidated. To visualize the crossroads between IT and CCD, we benefited from the fact that, in Phaseolus vulgaris nodulation, where the first division occurs in subepidermal cortical cells located underneath the infection site, we traced a Rhizobium etli strain expressing DsRed, the plant cytokinesis marker YFP-PvKNOLLE, a nuclear stain and cell wall auto-fluorescence. We found that the IT exits the root hair to penetrate an underlying subepidermal cortical (S-E) cell when it is concluding cytokinesis.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Buerger P, Vanstone RT, Maire J, et al (2022)

Long-Term Heat Selection of the Coral Endosymbiont Cladocopium C1acro (Symbiodiniaceae) Stabilizes Associated Bacterial Communities.

International journal of molecular sciences, 23(9):.

Heat-tolerant strains of the coral endosymbiont, Cladocopium C1acro (Symbiodiniaceae), have previously been developed via experimental evolution. Here, we examine physiological responses and bacterial community composition (using 16S rRNA gene metabarcoding) in cultures of 10 heat-evolved (SS) and 9 wild-type (WT) strains, which had been exposed for 6 years to 31 °C and 27 °C, respectively. We also examine whether the associated bacterial communities were affected by a three-week reciprocal transplantation to both temperatures. The SS strains had bacterial communities with lower diversities that showed more stability and lower variability when exposed to elevated temperatures compared with the WT strains. Amplicon sequence variants (ASVs) of the bacterial genera Labrenzia, Algiphilus, Hyphobacterium and Roseitalea were significantly more associated with the SS strains compared with the WT strains. WT strains showed higher abundance of ASVs assigned to the genera Fabibacter and Tropicimonas. We hypothesize that these compositional differences in associated bacterial communities between SS and WT strains also contribute to the thermal tolerance of the microalgae. Future research should explore functional potential between bacterial communities using metagenomics to unravel specific genomic adaptations.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Li YH, Yang YY, Wang ZG, et al (2022)

Emerging Function of Ecotype-Specific Splicing in the Recruitment of Commensal Microbiome.

International journal of molecular sciences, 23(9):.

In recent years, host-microbiome interactions in both animals and plants has emerged as a novel research area for studying the relationship between host organisms and their commensal microbial communities. The fitness advantages of this mutualistic interaction can be found in both plant hosts and their associated microbiome, however, the driving forces mediating this beneficial interaction are poorly understood. Alternative splicing (AS), a pivotal post-transcriptional mechanism, has been demonstrated to play a crucial role in plant development and stress responses among diverse plant ecotypes. This natural variation of plants also has an impact on their commensal microbiome. In this article, we review the current progress of plant natural variation on their microbiome community, and discuss knowledge gaps between AS regulation of plants in response to their intimately related microbiota. Through the impact of this article, an avenue could be established to study the biological mechanism of naturally varied splicing isoforms on plant-associated microbiome assembly.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Hatzios S (2022)

Metabolic Adaptation to Oxidative Stress at the Host-Microbe Interface.

FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 36 Suppl 1:.

Bacteria that chronically colonize the host must adapt to various forms of stress in the host environment. The molecular mechanisms bacteria use to sense and respond to these environmental signals are crucial for maintaining symbiotic associations with host cells. My laboratory uses chemical and biological tools to uncover new molecular mechanisms of bacterial adaptation to oxidative stress. In this talk, I will describe our recent discovery of a widely conserved transporter that enables microbial uptake of a diet-derived antioxidant from the host.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Rideb JR, Varghese A, Nguyen T, et al (2022)

Thermal Stress and Antioxidant Activity in Sea Anemones, Exaiptasia pallida.

FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 36 Suppl 1:.

When exposed to stress, coral reefs undergo bleaching, a process in which the host-symbiont relationship is disrupted. Stressors can be environmental including ocean acidification, exposure to ultraviolet radiation, or rising ocean temperatures due to global warming. The sea anemone, Exaiptasia pallida, serves as a model organism of coral reef biology since both species share symbiotic relationships with their algal symbionts and can undergo bleaching resulting in the expulsion of algal symbionts. This is the ultimate phenotypic result of high levels of stress experienced by the coral reef. Stress factors can lead to an increase in free radicals, like reactive oxygen species (ROS), that will adversely alter lipids, proteins, and DNA and trigger bleaching events. Although oxygen free radicals are natural by-products of metabolic processes in most organisms, they are closely regulated through endogenous systems, such as antioxidants like superoxide dismutase (SOD). We hypothesized that as temperatures increase, the levels of SOD activity in the sea anemone will increase over time. We used commercially available E. pallida to establish a 'stock' aquaria to rear anemones under optimal conditions for at least two weeks before use. The stock aquaria were maintained at 28-30% salinity at 22℃ during a 12-hour light/dark period, at a pH of approximately 8.4, with low levels nitrate, nitrite, and ammonia (checked weekly). E. pallida were moved from the stock tank and placed into one of three identical tanks, maintained at increasing temperatures of 22℃ (control), 24℃, and 29℃. We sampled 5 anemones from each tank at two-week intervals for 8 weeks. Seawater was removed by aspiration, anemones were weighed, flash-frozen in liquid nitrogen, and stored at -80℃. We extracted proteins from each sample by homogenization on ice. For each sample, total protein concentrations were established with a Bradford assay and SOD concentration in units of activity was established with a commercially available SOD assay. By observation, the anemones reared at in the higher range of thermal stress appeared smaller and individuals tended to die faster during the trial. E. pallida reared under increased temperatures of 24℃ and 29℃ showed an increase in SOD activity from week 6 to week 8 compared to the control tank at 22℃. These data are based on two replicates and further trials are currently in progress. Our findings describe the outcome of elevated temperature on levels of metabolism and increased levels of superoxide dismutase activity as a byproduct of stress. In addition, disruption of a host-symbiont relationship was suggested by the decrease in size and death of anemones at higher temperatures. Additional evidence is necessary to support our hypothesis and future experiments will focus on increasing the rearing time, increased temperatures, and other antioxidant defenses like xanthine oxidase or cyclooxygenases.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Davison HR, Pilgrim J, Wybouw N, et al (2022)

Genomic diversity across the Rickettsia and 'Candidatus Megaira' genera and proposal of genus status for the Torix group.

Nature communications, 13(1):2630.

Members of the bacterial genus Rickettsia were originally identified as causative agents of vector-borne diseases in mammals. However, many Rickettsia species are arthropod symbionts and close relatives of 'Candidatus Megaira', which are symbiotic associates of microeukaryotes. Here, we clarify the evolutionary relationships between these organisms by assembling 26 genomes of Rickettsia species from understudied groups, including the Torix group, and two genomes of 'Ca. Megaira' from various insects and microeukaryotes. Our analyses of the new genomes, in comparison with previously described ones, indicate that the accessory genome diversity and broad host range of Torix Rickettsia are comparable to those of all other Rickettsia combined. Therefore, the Torix clade may play unrecognized roles in invertebrate biology and physiology. We argue this clade should be given its own genus status, for which we propose the name 'Candidatus Tisiphia'.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Shimura H, Kim H, Matsuzawa A, et al (2022)

Coat protein of partitiviruses isolated from mycorrhizal fungi functions as an RNA silencing suppressor in plants and fungi.

Scientific reports, 12(1):7855.

Orchid seeds depend on colonization by orchid mycorrhizal (OM) fungi for their germination; therefore, the orchids and OM fungi have long maintained a close relationship (e.g., formation of the hyphal mass structure, peloton) during their evolution. In the present study, we isolated new partitiviruses from OM fungi; partitivirus were separately found in different subcultures from the same fungi. Partitiviruses have been believed to lack an RNA silencing suppressor (RSS), which is generally associated with viral pathogenicity, because most partitiviruses isolated so far are latent in both plants and fungi. However, we found that the coat protein (CP) of our partitiviruses indeed had RSS activity, which differed among the virus isolates from OM fungi; one CP showed RSS activity in both plants and fungi, while another CP showed no activity. The family Partitiviridae include viruses isolated from plants and fungi, and it has been suggested that these viruses may occasionally be transmitted between plant and fungal hosts. Given that there are several reports showing that viruses can adapt to nonhost using strong RSS, we here discussed the idea that partitiviruses may be better able to migrate between the orchid and fungus probably through the pelotons formed in the orchid cells, if host RNA silencing is suppressed by partitivirus RSS.

RevDate: 2022-05-17
CmpDate: 2022-05-17

Song L, Pan L, Jiang N, et al (2022)

Effects of endophytic fungi on parasitic process of Taxillus chinensis.

Scientific reports, 12(1):7744.

Taxillus chinensis (DC.) Danser is an extensively used medicinal shrub in the traditional as well as modern systems of medicines. It is a perennial hemiparasitic plant, which is difficult to propagate artificially because of its low parasitic rate. Successful parasitism of parasitic plants is to fuse their tissues and connect their vasculature to the host vasculature building a physiological bridge, which can efficiently withdraw water, sugars and nutrients from their host plants. It is reported that endophytic fungi play an important role in cell wall degradation and fusion, which is the key forming process of the physiological bridge. Therefore, in this study, the endophytic fungi from T. chinensis of different hosts were isolated, and then the organisms that could degrade the main components of the cell walls were screened out using a medium consisting of guaihuol and cellulose degradation capacity. The results showed that five strains were screened out from 72 endophytic fungi of T. chinensis which with high enzyme activities for lignocellulosic degradation. The laccase and cellulase activities of five strains reached their peaks at day 7, and the highest enzyme activities of these two enzymes were found in strain P6, which was 117.66 and 1.66 U/mL, respectively. Manganese peroxidase of strain 4 and lignin peroxidase of strain N6 also reached their peaks at day 7 and were the highest among the 5 strains, with enzyme activities of 11.61 and 6.64 U/mL, respectively. Strains 4, 15, 31, N6 and P6 were identified as Colletotrichum sp., Nigerrospora sphaerica, Exserohilum sp., Diaporthe phaseolorum and Pestalotiopsis sp., respectively, according to their morphological and molecular biology properties. The endophytic fungi may secrete efficient cell wall degradation enzymes, which promote the dissolution and relaxation of the cell wall between T. chinensis and host, thus contributing to the parasitism of T. chinensis.

RevDate: 2022-05-16

Vandegrift MA, RE Taylor-Piliae (2022)

Selecting a theoretical framework for chronic cardiovascular disease self-management among rural dwelling adults.

Applied nursing research : ANR, 65:151585.

A paucity of research has examined the factors and perceptions of self-management among individuals living rurally with chronic cardiovascular disease (CCVD). Exploration of this population is prudent as CCVD continues to be the leading cause of mortality within the United States (US). As the US population ages, increased rates of CCVD and the process of managing the disease will continue to challenge patients and the health care system. Rural dwelling adults are faced with additional complexities to manage a chronic disease, resulting in higher rates of chronic disease as compared to urban dwellers. It is essential for nurses working with adults living with CCVD in rural areas to promote self-management strategies derived from a theoretical perspective. The purpose of this paper is to examine theories and models that facilitate self-management of CCVD among rural dwelling adults. Three established self-management theories and models from psychology and public health were evaluated using Walker and Avant's framework for theory analysis. Social cognitive theory was selected as a best fit for self-management of CCVD among rural dwelling adults, due to the symbiosis of chronic disease, and applicability of ruralness within the triadic reciprocal causation of person-behavior-environment of the model.

RevDate: 2022-05-16

Um S, Lee J, SH Kim (2022)

Lobophorin Producing Endophytic Streptomyces olivaceus JB1 Associated With Maesa japonica (Thunb.) Moritzi & Zoll.

Frontiers in microbiology, 13:881253.

In this study, we focused on endophytes of Maesa japonica (Thunb.) Moritzi & Zoll. and the plant-microbe interaction at metabolite levels. We isolated seven endophytes associated with M. japonica (JB1-7), and focused on Streptomyces olivaceus JB1 because of antibacterial activities of its secondary metabolites. We confirmed lobophorin analogs production from the bacterial strain JB1 by using spectroscopic techniques such as NMR, UV, and LC/Q-TOF-MS. In the LC/MS system, thirteen reported lobophorin analogs and twelve unreported analogs were detected. Among metabolites, lobophorin A was clearly detected in the dried foliar residues of M. japonica which implies that JB1 resides in the host and accumulates its secondary metabolites likely interacting with the plant. Antimicrobial activity tests of the secondary metabolites against undesirable contaminants isolated from the external surface of M. japonica supported the host and microbe mutualistic relationship. In the meantime, lobophorin producing Streptomyces spp. were isolated from marine environments such as marine sediments, algae, corals, and sponges. As lobophorin producing Streptomyces is isolated commonly from marine environments, we conducted a saline water stress tolerance test with JB1 showing saline medium does not accelerate the growth of the bacterium.

RevDate: 2022-05-16

Grossman AS, Escobar CA, Mans EJ, et al (2022)

A Surface Exposed, Two-Domain Lipoprotein Cargo of a Type XI Secretion System Promotes Colonization of Host Intestinal Epithelia Expressing Glycans.

Frontiers in microbiology, 13:800366.

The only known required component of the newly described Type XI secretion system (TXISS) is an outer membrane protein (OMP) of the DUF560 family. TXISSOMPs are broadly distributed across proteobacteria, but properties of the cargo proteins they secrete are largely unexplored. We report biophysical, histochemical, and phenotypic evidence that Xenorhabdus nematophila NilC is surface exposed. Biophysical data and structure predictions indicate that NilC is a two-domain protein with a C-terminal, 8-stranded β-barrel. This structure has been noted as a common feature of TXISS effectors and may be important for interactions with the TXISSOMP. The NilC N-terminal domain is more enigmatic, but our results indicate it is ordered and forms a β-sheet structure, and bioinformatics suggest structural similarities to carbohydrate-binding proteins. X. nematophila NilC and its presumptive TXISSOMP partner NilB are required for colonizing the anterior intestine of Steinernema carpocapsae nematodes: the receptacle of free-living, infective juveniles and the anterior intestinal cecum (AIC) in juveniles and adults. We show that, in adult nematodes, the AIC expresses a Wheat Germ Agglutinin (WGA)-reactive material, indicating the presence of N-acetylglucosamine or N-acetylneuraminic acid sugars on the AIC surface. A role for this material in colonization is supported by the fact that exogenous addition of WGA can inhibit AIC colonization by X. nematophila. Conversely, the addition of exogenous purified NilC increases the frequency with which X. nematophila is observed at the AIC, demonstrating that abundant extracellular NilC can enhance colonization. NilC may facilitate X. nematophila adherence to the nematode intestinal surface by binding to host glycans, it might support X. nematophila nutrition by cleaving sugars from the host surface, or it might help protect X. nematophila from nematode host immunity. Proteomic and metabolomic analyses of wild type X. nematophila compared to those lacking nilB and nilC revealed differences in cell wall and secreted polysaccharide metabolic pathways. Additionally, purified NilC is capable of binding peptidoglycan, suggesting that periplasmic NilC may interact with the bacterial cell wall. Overall, these findings support a model that NilB-regulated surface exposure of NilC mediates interactions between X. nematophila and host surface glycans during colonization. This is a previously unknown function for a TXISS.

RevDate: 2022-05-16

Elhaissoufi W, Ghoulam C, Barakat A, et al (2022)

Phosphate bacterial solubilization: A key rhizosphere driving force enabling higher P use efficiency and crop productivity.

Journal of advanced research, 38:13-28 pii:S2090-1232(21)00167-3.

Background: Increasing crop production to feed a growing population has driven the use of mineral fertilizers to ensure nutrients availability and fertility of agricultural soils. After nitrogen, phosphorus (P) is the second most important nutrient for plant growth and productivity. However, P availability in most agricultural soils is often limited because P strongly binds to soil particles and divalent cations forming insoluble P-complexes. Therefore, there is a constant need to sustainably improve soil P availability. This may include, among other strategies, the application of microbial resources specialized in P cycling, such as phosphate solubilizing bacteria (PSB). This P-mediating bacterial component can improve soil biological fertility and crop production, and should be integrated in well-established formulations to enhance availability and efficiency in use of P. This is of importance to P fertilization, including both organic and mineral P such as rock phosphate (RP) aiming to improve its agronomic efficiency within an integrated crop nutrition system where agronomic profitability of P and PSB can synergistically occur.

Aim of Review: The purpose of this review is to discuss critically the important contribution of PSB to crop P nutrition in concert with P fertilizers, with a specific focus on RP. We also highlight the need for PSB bioformulations being a sustainable approach to enhance P fertilizer use efficiency and crop production.

We first recognize the important contribution of PSB to sustain crop production, which requires a rational approach for both screening and evaluation of PSB enabling an accurate assessment of the bacterial effects both alone and in intertwined interaction with plant roots. Furthermore, we propose new research ideas about the development of microbial bioformulations based on PSB with a particular focus on strains exhibiting synergetic effects with RP.

RevDate: 2022-05-16

Wilta F, Chong ALC, Selvachandran G, et al (2022)

Generalized Susceptible-Exposed-Infectious-Recovered model and its contributing factors for analyzing the death and recovery rates of the COVID-19 pandemic.

Applied soft computing pii:S1568-4946(22)00310-6 [Epub ahead of print].

COVID-19 is a highly contagious disease that has infected over 136 million people worldwide with over 2.9 million deaths as of 11 April 2021. In March 2020, the WHO declared COVID-19 as a pandemic and countries began to implement measures to control the spread of the virus. The spread and the death rates of the virus displayed dramatic differences among countries globally, showing that there are several factors affecting its spread and mortality. By utilizing the cumulative number of cases from John Hopkins University, the recovery rate, death rate, and the number of active, recovered, and death cases were simulated to analyze the trends and patterns within the chosen countries. 10 countries from 3 different case severity categories (high cases, medium cases, and low cases) and 5 continents (Asia, North America, South America, Europe, and Oceania) were studied. A generalized SEIR model which considers control measures such as isolation, and preventive measures such as vaccination is applied in this study. This model is able to capture not only the dynamics between the states, but also the time evolution of the states by using the fourth-order-Runge-Kutta process. This study found no significant patterns in the countries under the same case severity category, suggesting that there are other factors contributing to the pattern in these countries. One of the factors influencing the pattern in each country is the population's age. COVID-19 related deaths were found to be notably higher among older people, indicating that countries comprising of a larger proportion of older age groups have an increased risk of experiencing higher death rates. Tighter governmental control measures led to fewer infections and eventually reduced the number of death cases, while increasing the recovery rate, and early implementations were found to be far more effective in controlling the spread of the virus and produced better outcomes.

RevDate: 2022-05-16

Cho G, Gang GH, Jung HY, et al (2022)

Exploration of Mycobiota in Cypripedium japonicum, an Endangered Species.

Mycobiology, 50(2):142-149 pii:2064409.

Orchids live with mycorrhizal fungi in mutualism. This symbiotic relationship plays an essential role in the overall life cycle of orchids from germination, growth, settlement, and reproduction. Among the 1000 species of the orchid, the Korean lady's slipper, Cypripedium japonicum, is known as an endangered species. Currently, only five natural habitats of the Korean lady's slipper remain in South Korea, and the population of Korean lady's slipper in their natural habitat is not increasing. To prevent extinction, this study was designed to understand the fungal community interacting in the rhizosphere of the Korean lady's slipper living in the native and artificial habitats. In-depth analyses were performed to discover the vital mycorrhizal fungi contributing to habitat expansion and cultivation of the endangered orchid species. Our results suggested that Lycoperdon nigrescens contributed most to the increase in natural habitats and Russula violeipes as a characteristic of successful cultivation. And the fungi that helped L. nigrescens and R. violeipes to fit into the rhizosphere community in Korean lady's slipper native place were Paraboeremia selaginellae and Metarhizium anisopliae, respectively. The findings will contribute to restoring and maintaining the endangered orchid population in natural habitats.

RevDate: 2022-05-16

Gwon JH, Park H, AH Eom (2022)

Mycorrhization of Quercus spp. with Tuber huidongense and T. himalayense Collected in Korea.

Mycobiology, 50(2):104-109 pii:2065717.

Fungi of the genus Tuber are ectomycorrhizal fungi that form a symbiotic relationship mainly with oak and hazel trees. Tuber spp. exhibit a highly selective host plant preference; thus, for cultivation purposes it is important to select an appropriate host plant for successful mycorrhization. In addition, as mycorrhizal characteristics differ according to Tuber spp., it is necessary to understand the differences in mycorrhizae according to the fungal species. Tuber huidongense and Tuber himalayense were recently discovered in Korea; therefore, we used spore suspensions from these two species to inoculate two species of oak trees, Quercus acutissima and Quercus dentata, to compare colonization rates and morphologies of the mycorrhizae. The colonization rates demonstrated that the different Tuber spp. favored different host plant species. In addition, unique morphological and anatomical characteristics were observed for T. huidongense and T. himalayense depending on the host species. These findings can lead to new economically important agricultural activities related to truffle cultivation in Korea.

RevDate: 2022-05-15

Cummins NW, AD Badley (2022)

Could proteasome inhibition improve therapeutic vaccine response in HIV?.

Vaccine pii:S0264-410X(22)00578-3 [Epub ahead of print].

RevDate: 2022-05-15

Matsubara A, Nomura A, T Yamaguchi (2022)


Arerugi = [Allergy], 71(3):191-194.

RevDate: 2022-05-15

Xu L, Wang J, Xiao Y, et al (2022)

Structural insight into chitin perception by chitin elicitor receptor kinase 1 of Oryza sativa.

Journal of integrative plant biology [Epub ahead of print].

Plants have developed innate immune systems to fight against pathogenic fungi by monitoring pathogenic signals known as pathogen-associated molecular patterns (PAMP) and have established endo symbiosis with arbuscular mycorrhizal (AM) fungi through recognition of mycorrhizal (Myc) factors. Chitin elicitor receptor kinase 1 of Oryza sativa subsp. Japonica (OsCERK1) plays a bifunctional role in mediating both chitin-triggered immunity and symbiotic relationships with AM fungi. However, it remains unclear whether OsCERK1 can directly recognize chitin molecules. In this study, we show that OsCERK1 binds to the chitin hexamer ((NAG)6) and tetramer ((NAG)4) directly and determine the crystal structure of the OsCERK1-(NAG)6 complex at 2 Å. The structure shows that one OsCERK1 is associated with one (NAG)6 . Upon recognition, chitin hexamer binds OsCERK1 by interacting with the shallow groove on the surface of LysM2. These structural findings, complemented by mutational analyses, demonstrate that LysM2 is crucial for recognition of both (NAG)6 and (NAG)4 . Altogether, these findings provide structural insights into the ability of OsCERK1 in chitin perception, which will lead to a better understanding of the role of OsCERK1 in mediating both immunity and symbiosis in rice. This article is protected by copyright. All rights reserved.

RevDate: 2022-05-14

Feng J, Lv W, Xu J, et al (2022)

Overlapping Root Architecture and Gene Expression of Nitrogen Transporters for Nitrogen Acquisition of Tomato Plants Colonized with Isolates of Funneliformis mosseae in Hydroponic Production.

Plants (Basel, Switzerland), 11(9): pii:plants11091176.

Understanding the impact of arbuscular mycorrhizal fungi (AMF) upon the nitrogen (N) uptake of tomato (Lycopersicum esculentum L.) plants is crucial for effectively utilizing these beneficial microorganisms in industrial hydroponic tomato production. Yet it remains unknown whether, besides fungal delivery, the AMF also affects N uptake via altered plant root growth or whether, together with changed N transporters expression of hosts, this impact is isolate-specific. We investigated tomato root architecture and the expression of LeAMT1.1, LeAMT1.2, and LeNRT2.3 genes in roots inoculated with five isolates of Funneliformis mosseae, these collected from different geographical locations, under greenhouse conditions with nutritional solution in coconut coir production. Our results revealed that isolate-specific AMF inoculation strongly increased the root biomass, total root length, surface area, and volume. Linear relationships were found between the total root length and N accumulation in plants. Furthermore, expression levels of LeAMT1.1, LeAMT1.2, and LeNRT2.3 were significantly up-regulated by inoculation with F. mosseae with isolate-specific. These results implied N uptake greater than predicted by root growth, and N transporters up-regulated by AMF symbiosis in an isolate-specific manner. Thus, an overlap in root biomass, architecture and expression of N transporters increase N acquisition in tomato plants in the symbiosis.

RevDate: 2022-05-14

Flores-Duarte NJ, Mateos-Naranjo E, Redondo-Gómez S, et al (2022)

Role of Nodulation-Enhancing Rhizobacteria in the Promotion of Medicago sativa Development in Nutrient-Poor Soils.

Plants (Basel, Switzerland), 11(9): pii:plants11091164.

Legumes are usually used as cover crops to improve soil quality due to the biological nitrogen fixation that occurs due to the interaction of legumes and rhizobia. This symbiosis can be used to recover degraded soils using legumes as pioneer plants. In this work, we screened for bacteria that improve the legume-rhizobia interaction in nutrient-poor soils. Fourteen phosphate solubilizer-strains were isolated, showing at least three out of the five tested plant growth promoting properties. Furthermore, cellulase, protease, pectinase, and chitinase activities were detected in three of the isolated strains. Pseudomonas sp. L1, Chryseobacterium soli L2, and Priestia megaterium L3 were selected to inoculate seeds and plants of Medicago sativa using a nutrient-poor soil as substrate under greenhouse conditions. The effects of the three bacteria individually and in consortium showed more vigorous plants with increased numbers of nodules and a higher nitrogen content than non-inoculated plants. Moreover, bacterial inoculation increased plants' antioxidant activities and improved their development in nutrient-poor soils, suggesting an important role in the stress mechanisms of plants. In conclusion, the selected strains are nodulation-enhancing rhizobacteria that improve leguminous plants growth and nodulation in nutrient-poor soils and could be used by sustainable agriculture to promote plants' development in degraded soils.

RevDate: 2022-05-14

Jēkabsone A, Andersone-Ozola U, Karlsons A, et al (2022)

Dependence on Nitrogen Availability and Rhizobial Symbiosis of Different Accessions of Trifolium fragiferum, a Crop Wild Relative Legume Species, as Related to Physiological Traits.

Plants (Basel, Switzerland), 11(9): pii:plants11091141.

Biological nitrogen fixation by legume-rhizobacterial symbiosis in temperate grasslands is an important source of soil nitrogen. The aim of the present study was to characterize the dependence of different accessions of T. fragiferum, a rare crop wild relative legume species, from their native rhizobia as well as additional nitrogen fertilization in controlled conditions. Asymbiotically cultivated, mineral-fertilized T. fragiferum plants gradually showed signs of nitrogen deficiency, appearing as a decrease in leaf chlorophyll concentration, leaf senescence, and a decrease in growth rate. The addition of nitrogen, and the inoculation with native rhizobia, or both treatments significantly prevented the onset of these symptoms, leading to both increase in plant shoot biomass as well as an increase in tissue concentration of N. The actual degree of each type of response was genotype-specific. Accessions showed a relatively similar degree of dependence on nitrogen (70-95% increase in shoot dry mass) but the increase in shoot dry mass by inoculation with native rhizobia ranged from 27 to 85%. In general, there was no correlation between growth stimulation and an increase in tissue N concentration by the treatments. The addition of N or rhizobial inoculant affected mineral nutrition at the level of both macronutrient and micronutrient concentration in different plant parts. In conclusion, native rhizobial strains associated with geographically isolated accessions of T. fragiferum at the northern range of distribution of the species represent a valuable resource for further studies aimed at the identification of salinity-tolerant N2-fixing bacteria for the needs of sustainable agriculture, as well as in a view of understanding ecosystem functioning at the level of plant-microorganism interactions.

RevDate: 2022-05-14

Nascimento LBDS, M Tattini (2022)

Beyond Photoprotection: The Multifarious Roles of Flavonoids in Plant Terrestrialization.

International journal of molecular sciences, 23(9): pii:ijms23095284.

Plants evolved an impressive arsenal of multifunctional specialized metabolites to cope with the novel environmental pressures imposed by the terrestrial habitat when moving from water. Here we examine the multifarious roles of flavonoids in plant terrestrialization. We reason on the environmental drivers, other than the increase in UV-B radiation, that were mostly responsible for the rise of flavonoid metabolism and how flavonoids helped plants in land conquest. We are reasonably based on a nutrient-deficiency hypothesis for the replacement of mycosporine-like amino acids, typical of streptophytic algae, with the flavonoid metabolism during the water-to-land transition. We suggest that flavonoids modulated auxin transport and signaling and promoted the symbiosis between plants and fungi (e.g., arbuscular mycorrhizal, AM), a central event for the conquest of land by plants. AM improved the ability of early plants to take up nutrients and water from highly impoverished soils. We offer evidence that flavonoids equipped early land plants with highly versatile "defense compounds", essential for the new set of abiotic and biotic stressors imposed by the terrestrial environment. We conclude that flavonoids have been multifunctional since the appearance of plants on land, not only acting as UV filters but especially improving both nutrient acquisition and biotic stress defense.

RevDate: 2022-05-14

Parejo S, Cabrera JJ, Jiménez-Leiva A, et al (2022)

Fine-Tuning Modulation of Oxidation-Mediated Posttranslational Control of Bradyrhizobium diazoefficiens FixK2 Transcription Factor.

International journal of molecular sciences, 23(9): pii:ijms23095117.

FixK2 is a CRP/FNR-type transcription factor that plays a central role in a sophisticated regulatory network for the anoxic, microoxic and symbiotic lifestyles of the soybean endosymbiont Bradyrhizobium diazoefficiens. Aside from the balanced expression of the fixK2 gene under microoxic conditions (induced by the two-component regulatory system FixLJ and negatively auto-repressed), FixK2 activity is posttranslationally controlled by proteolysis, and by the oxidation of a singular cysteine residue (C183) near its DNA-binding domain. To simulate the permanent oxidation of FixK2, we replaced C183 for aspartic acid. Purified C183D FixK2 protein showed both low DNA binding and in vitro transcriptional activation from the promoter of the fixNOQP operon, required for respiration under symbiosis. However, in a B. diazoefficiens strain coding for C183D FixK2, expression of a fixNOQP'-'lacZ fusion was similar to that in the wild type, when both strains were grown microoxically. The C183D FixK2 encoding strain also showed a wild-type phenotype in symbiosis with soybeans, and increased fixK2 gene expression levels and FixK2 protein abundance in cells. These two latter observations, together with the global transcriptional profile of the microoxically cultured C183D FixK2 encoding strain, suggest the existence of a finely tuned regulatory strategy to counterbalance the oxidation-mediated inactivation of FixK2 in vivo.

RevDate: 2022-05-13

Ahlawat A, Khan AA, Deshmukh P, et al (2022)

Strain assisted magnetoelectric coupling in ordered nanomagnets of CoFe2O4/SrRuO3/(Pb(Mg1/3Nb2/3)O3-PbTiO3) hetrostructures.

Journal of physics. Condensed matter : an Institute of Physics journal [Epub ahead of print].

We have explored the electric field controlled magnetization in the nanodot CoFe2O4/SrRuO3/PMN-PT heterostructures. Ordered ferromagnetic CFO nanodots (~300 nm lateral dimension) are developed on the PMN-PT substrate (ferroelectric as well as piezoelectric) using a nanostencil-mask pattering method during pulsed laser deposition. The nanostructures reveal electric field induced magnetization reversal in the single domain CFO nanodots through transfer of the piezostrains from the piezoelectric PMN-PT substrate to the CFO. Further, electric field modulated spin structure of CFO nanomagnets is analysed by using X-ray magnetic circular dichroism (XMCD). The XMCD analysis divulge cations (Fe3+/Co2+) redistribution on octahedral and tetrahedral site in the electric field poled CoFe2O4 nanodots, establishing the strain induced magneto-electric coupling effects.The CoFe2O4/SrRuO3/PMN-PT nanodots structure demonstrate multilevel switching of ME coupling coefficient (α) by applying selective positive and negative electric fields in a non-volatile manner. The retention of two stable states of α is illustrated for ~106seconds, which can be employedto store digital datain non-volatile memory devices. Thus the voltage controlled magnetization in the nanodot structures leads a path towards the invention of energy efficient high-density memory devices.

RevDate: 2022-05-13

Shahid M, Ahmed B, Zaidi A, et al (2018)

Toxicity of fungicides to Pisum sativum: a study of oxidative damage, growth suppression, cellular death and morpho-anatomical changes.

RSC advances, 8(67):38483-38498 pii:c8ra03923b.

Considering the fungicidal threat to the sustainable agro-environment, the toxicological impacts of three fungicides, namely kitazin, hexaconazole and carbendazim, on the biological, chemical and morpho-anatomical changes of peas were assessed. Fungicide applications in general caused a slow but gradual reduction in growth, symbiosis and yields of peas, which, however, varied appreciably among species and concentrations of the three fungicides. Of the three fungicides, carbendazim had the most lethal effect, in which it delayed seed germination and also diminished the overall pea growth. Carbendazim at 3000 μg kg-1 maximally reduced the germination, SVI, size of roots and shoots and total dry matter accumulation in roots, shoots and whole plants distinctly by 40%, 84%, 72%, 73%, 68%, 75% and 73% (p ≤ 0.05), respectively. Hexaconazole at 120 μg kg-1 significantly (p ≤ 0.05) declined total chlorophyll, carotenoids, grain yields, grain protein, root P and shoot N by 19%, 28%, 46%, 69%, 48% and 51%, respectively, over the control. The synthesis of stress biomarkers and oxidative stress were increased with increasing dosage rates of fungicides. Proline content in roots, shoots, leaves and grains, MDA, electrolyte leakage and H2O2 of plants grown in soil treated with 288 μg kg-1 kitazin were increased significantly (p ≤ 0.05) by 73%, 52%, 41%, 24%, 59%, 40% and 27%, respectively, relative to the control. Antioxidant defence enzymes were greater in pea foliage. The SEM and CLSM images revealed an obvious alteration in root tips, enhanced cellular damage and cell death when plants were raised under fungicide stress. Also, morpho-anatomical variations in fungicide-treated foliage were visible in the SEM images. Overall, the present study suggests that a careful and secure strategy should be adopted before fungicides are chosen for enhancing pulse production in different agro-climatic regions.

RevDate: 2022-05-13

Kitaeva AB, Gorshkov AP, Kusakin PG, et al (2022)

Tubulin Cytoskeleton Organization in Cells of Determinate Nodules.

Frontiers in plant science, 13:823183.

Plant cell differentiation is based on rearrangements of the tubulin cytoskeleton; this is also true for symbiotic nodules. Nevertheless, although for indeterminate nodules (with a long-lasting meristem) the organization of microtubules during nodule development has been studied for various species, for determinate ones (with limited meristem activity) such studies are rare. Here, we investigated bacteroid morphology and dynamics of the tubulin cytoskeleton in determinate nodules of four legume species: Glycine max, Glycine soja, Phaseolus vulgaris, and Lotus japonicus. The most pronounced differentiation of bacteroids was observed in G. soja nodules. In meristematic cells in incipient nodules of all analyzed species, the organization of both cortical and endoplasmic microtubules was similar to that described for meristematic cells of indeterminate nodules. In young infected cells in developing nodules of all four species, cortical microtubules formed irregular patterns (microtubules were criss-crossed) and endoplasmic ones were associated with infection threads and infection droplets. Surprisingly, in uninfected cells the patterns of cortical microtubules differed in nodules of G. max and G. soja on the one hand, and P. vulgaris and L. japonicus on the other. The first two species exhibited irregular patterns, while the remaining two exhibited regular ones (microtubules were oriented transversely to the longitudinal axis of cell) that are typical for uninfected cells of indeterminate nodules. In contrast to indeterminate nodules, in mature determinate nodules of all four studied species, cortical microtubules formed a regular pattern in infected cells. Thus, our analysis revealed common patterns of tubulin cytoskeleton in the determinate nodules of four legume species, and species-specific differences were associated with the organization of cortical microtubules in uninfected cells. When compared with indeterminate nodules, the most pronounced differences were associated with the organization of cortical microtubules in nitrogen-fixing infected cells. The revealed differences indicated a possible transition during evolution of infected cells from anisotropic growth in determinate nodules to isodiametric growth in indeterminate nodules. It can be assumed that this transition provided an evolutionary advantage to those legume species with indeterminate nodules, enabling them to host symbiosomes in their infected cells more efficiently.

RevDate: 2022-05-13

Lo R, Dougan KE, Chen Y, et al (2022)

Alignment-Free Analysis of Whole-Genome Sequences From Symbiodiniaceae Reveals Different Phylogenetic Signals in Distinct Regions.

Frontiers in plant science, 13:815714.

Dinoflagellates of the family Symbiodiniaceae are predominantly essential symbionts of corals and other marine organisms. Recent research reveals extensive genome sequence divergence among Symbiodiniaceae taxa and high phylogenetic diversity hidden behind subtly different cell morphologies. Using an alignment-free phylogenetic approach based on sub-sequences of fixed length k (i.e. k-mers), we assessed the phylogenetic signal among whole-genome sequences from 16 Symbiodiniaceae taxa (including the genera of Symbiodinium, Breviolum, Cladocopium, Durusdinium and Fugacium) and two strains of Polarella glacialis as outgroup. Based on phylogenetic trees inferred from k-mers in distinct genomic regions (i.e. repeat-masked genome sequences, protein-coding sequences, introns and repeats) and in protein sequences, the phylogenetic signal associated with protein-coding DNA and the encoded amino acids is largely consistent with the Symbiodiniaceae phylogeny based on established markers, such as large subunit rRNA. The other genome sequences (introns and repeats) exhibit distinct phylogenetic signals, supporting the expected differential evolutionary pressure acting on these regions. Our analysis of conserved core k-mers revealed the prevalence of conserved k-mers (>95% core 23-mers among all 18 genomes) in annotated repeats and non-genic regions of the genomes. We observed 180 distinct repeat types that are significantly enriched in genomes of the symbiotic versus free-living Symbiodinium taxa, suggesting an enhanced activity of transposable elements linked to the symbiotic lifestyle. We provide evidence that representation of alignment-free phylogenies as dynamic networks enhances the ability to generate new hypotheses about genome evolution in Symbiodiniaceae. These results demonstrate the potential of alignment-free phylogenetic methods as a scalable approach for inferring comprehensive, unbiased whole-genome phylogenies of dinoflagellates and more broadly of microbial eukaryotes.

RevDate: 2022-05-13

Patel SU, Hauser P, J Ronan (2022)

Metabolomic Signatures of Ocean Acidification Stress in the Coral Acropora millepora.

FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 36 Suppl 1:.

The rapid acidification of seawater poses a significant threat to the persistence of coral reefs. However, taxa-specific, mechanistic understandings of holobiont responses to ocean acidification (OA) stress remain largely unknown. Understanding these mechanisms is crucial to uncovering predictive markers of OA stress. This could subsequently be used to assist field-based conservation efforts. We hypothesized that exposure to elevated pCO2 levels would decrease the abundance of primary metabolites such as amino acids and carbohydrates and increase the production of secondary metabolites, specifically those involved in cnidarian-symbiodinium cell signaling. In this study, we applied untargeted capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS) to profile changes in the intracellular polar and semi-polar metabolite composition of the coral holobiont after exposure to elevated pCO2 concentrations. Nubbins of Acropora millepora were exposed to ambient (410 µatm) or elevated (805 µatm) pCO2 levels under controlled conditions over a period of 10 days. Measurement of treatment-induced bleaching was performed by quantification of symbiodinium cell density and chlorophyll a concentration. We hope to identify molecules in the metabolite profiles associated with the individual cellular responses of holobiont members to osmotic stress. Additionally, we hope to provide further insight into unknown roles of secondary and tertiary metabolite pools in cellular homeostasis and acclimation to thermal stress in the coral holobiont, and specifically the cnidarian-symbiodinium symbiosis. Our goal is for these findings to assist conservation efforts, specifically in the development of rapid tests for field-based conservation efforts.

RevDate: 2022-05-13

Toyoda HC, Chen S, MB Berkmen (2022)

Role of ConE's ATPase Motifs in Protein-Protein Interactions within the Conjugation Machinery of Bacillus subtilis.

FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 36 Suppl 1:.

Conjugation is the transfer of DNA from one bacterial cell to another. Conjugation is a major form of horizontal gene transfer, resulting in the spread of genes that play roles in antibiotic resistance, virulence, symbiosis and metabolism. ICEBs1 is an integrative and conjugative element of Bacillus subtilis. The conjugation machinery that transfers DNA is a Type 4 Secretion System (T4SS). The ICEBs1 T4SS includes the proteins ConB, ConC, ConD, ConE, ConG, ConQ, and CwlT. The focus of our work is the ConE peripheral membrane protein, which belongs to the VirB4 family of ATPases. We analyzed whether ConE interacts with any of the other ICEBs1 T4SS proteins using bacterial two hybrid (BACTH). We found that ConE interacts with itself, ConB, and ConQ. We used site-directed mutagenesis of the conE gene to make alanine substitutions within five conserved residues within ATPase motifs of the ConE protein that have previously been shown to be critical for mating. We used BACTH to determine if these mutations affect ConE's protein interactions. We discovered that interaction of ConE with itself or ConB is unaffected by mutations in any of the ATPase residues tested, but that the ConE-ConQ interaction depends on two conserved residues within the ATPase motifs. Our research sheds new light on the role of conserved residues within the ATPase motifs of ConE.

RevDate: 2022-05-13

Chakraborty S, Valdés-López O, Stonoha-Arther C, et al (2022)

Transcription Factors Controlling the Rhizobium-Legume Symbiosis: Integrating Infection, Organogenesis, and the Abiotic Environment.

Plant & cell physiology pii:6584650 [Epub ahead of print].

Legume roots engage in a symbiotic relationship with rhizobia leading to the development of nitrogen-fixing nodules. Nodule development is a sophisticated process and is under the tight regulation of the plant. The symbiosis initiates with a signal exchange between the two partners, followed by the development of a new organ colonized by rhizobia. Over two decades of study have shed light on the transcriptional regulation of rhizobium-legume symbiosis. A large number of transcription factors (TFs) have been implicated in one or more stages of this symbiosis. Legumes must monitor nodule development amidst a dynamic physical environment. Some environmental factors are conducive to nodulation, whereas others are stressful. The modulation of rhizobium-legume symbiosis by the abiotic environment adds another layer of complexity and is also transcriptionally regulated. Several symbiotic TFs act as integrators between symbiosis and the response to the abiotic environment. In this review, we trace the role of various TFs involved in rhizobium-legume symbiosis along its developmental route and highlight the ones that also act as communicators between this symbiosis and the response to the abiotic environment. Finally, we discuss contemporary approaches to study TF-target interactions in plants and probe their potential utility in the field of rhizobium-legume symbiosis.

RevDate: 2022-05-13

Ji X, Xia Y, Zhang H, et al (2022)

The microscopic mechanism between endophytic fungi and host plants: From recognition to building stable mutually beneficial relationships.

Microbiological research, 261:127056 pii:S0944-5013(22)00096-9 [Epub ahead of print].

Growing research suggests that endophytic fungi deeply affect plant physiology, development, and metabolism, which has become an indispensable subject in plant research. However, the micromolecular mechanisms remain vague due to the complexity of the interactions. This article summarizes the latest progress in the mechanism studies of the symbiotic relationships between endophytic fungi and plants. We address the aspects from signal generation, plant defense, to fungal coping strategies to establish the balanced constraint relationships between fungi and their hosts that finally form "a community of shared future." These processes do not occur in isolation but in synergy. Both endophytic fungi and their host plants contribute to establishing the stable symbiosis. New insights have been provided into a deeper understanding of the occurrence of species interactions and their applications to solving practical problems.

RevDate: 2022-05-13

Teli P, Kale V, A Vaidya (2022)

Mesenchymal stromal cells-derived secretome protects Neuro-2a cells from oxidative stress-induced loss of neurogenesis.

Experimental neurology pii:S0014-4886(22)00132-7 [Epub ahead of print].

Neurodegenerative diseases (ND) are characterized by debilitating medical conditions that principally affect the neuronal cells in the human brain. One of the major reasons that there are no effective drugs for the treatment of ND is because researchers face technical challenges while conducting studies to understand the molecular mechanism behind ND. Although various studies have established in vitro neurodegenerative model systems, we feel that these model systems are not physiologically relevant, as they do not mimic the in vivo situation of chronic insult. Therefore, the primary aim of this study was to establish an in vitro neurodegenerative model system by inducing oxidative stress in such a way that the neuronal cells remain viable, but lose their structural and functional characteristics. Using a murine neuroblastoma cell line, Neuro-2a, we demonstrate that induction of oxidative stress significantly affects various neurite outgrowth parameters and reduces the expression of neuronal and autophagy markers without causing apoptosis in them. Previously, we have discussed the possible therapeutic applications of mesenchymal stromal cells (MSCs) and their secretome in the treatment of ND. Here, using two distinct approaches, we show that when Neuro-2a cells subjected to oxidative stress are exposed to MSC-derived conditioned medium (secretome), they exhibit a significant improvement in various neuronal parameters and in the expression of neuronal markers. Overall, our findings support the salutary role of MSC-derived secretome in rescuing the oxidative stress-induced loss of neurogenesis using a physiologically relevant in vitro model system. Our data underscore the propensity of the MSC-secretome in reversing ND.

RevDate: 2022-05-13

Cui G, Liew YJ, Konciute MK, et al (2022)

Nutritional control regulates symbiont proliferation and life history in coral-dinoflagellate symbiosis.

BMC biology, 20(1):103.

BACKGROUND: The coral-Symbiodiniaceae symbiosis is fundamental for the coral reef ecosystem. Corals provide various inorganic nutrients to their algal symbionts in exchange for the photosynthates to meet their metabolic demands. When becoming symbionts, Symbiodiniaceae cells show a reduced proliferation rate and a different life history. While it is generally believed that the animal hosts play critical roles in regulating these processes, far less is known about the molecular underpinnings that allow the corals to induce the changes in their symbionts.

RESULTS: We tested symbiont cell proliferation and life stage changes in vitro in response to different nutrient-limiting conditions to determine the key nutrients and to compare the respective symbiont transcriptomic profiles to cells in hospite. We then examined the effects of nutrient repletion on symbiont proliferation in coral hosts and quantified life stage transitions in vitro using time-lapse confocal imaging. Here, we show that symbionts in hospite share gene expression and pathway activation profiles with free-living cells under nitrogen-limited conditions, strongly suggesting that symbiont proliferation in symbiosis is limited by nitrogen availability.

CONCLUSIONS: We demonstrate that nitrogen limitation not only suppresses cell proliferation but also life stage transition to maintain symbionts in the immobile coccoid stage. Nutrient repletion experiments in corals further confirmed that nitrogen availability is the major factor limiting symbiont density in hospite. Our study emphasizes the importance of nitrogen in coral-algae interactions and, more importantly, sheds light on the crucial role of nitrogen in symbiont life history regulation.

RevDate: 2022-05-13

Bastías DA, Gundel PE, Johnson RD, et al (2022)

How and when fungal endophytes can eliminate the plant growth-defence trade-off: mechanistic perspectives: A response to Atala et al. (2022) 'Fungal endophytes improve the performance of host plants but do not eliminate the growth/defence trade-off'.

RevDate: 2022-05-13

Saura JR, Dwivedi YK, D Palacios-Marqués (2022)

Editorial: Online User Behavior and User-Generated Content.

Frontiers in psychology, 13:895467.

RevDate: 2022-05-13

Thakur H, Pareek P, Sayyad MG, et al (2022)

Association of Premenstrual Syndrome with Adiposity and Nutrient Intake Among Young Indian Women.

International journal of women's health, 14:665-675 pii:359458.

Abstract: Premenstrual syndrome (PMS) refers to a heterogenous group of symptoms occurring in luteal phase of the menstrual cycle. Women of childbearing age are affected by PMS, and it may impact their quality of life. Various factors related to the biology of menstruation, hormones, and lifestyle are associated with PMS.

Purpose: To explore the incidence and severity of PMS among students in India and its correlation with nutrient intake, adiposity, and lifestyle factors.

Methods: A semi-structured questionnaire was used to collect data on menstrual pattern, nutrient intake, dietary habits, and physical activity. Moose's Menstrual Distress Questionnaire and Premenstrual Symptoms Screening Tool were employed for the identification and classification of PMS. Anthropometric indices included height, weight, body mass index, waist circumference, hip circumference, waist-to-hip ratio, and four-site skinfold thickness-tricep, bicep, subscapular, and suprailiac.

Results: Of the 330 participants, 71.3% reported to have experienced at least one symptom of PMS. Furthermore, 46.9% had mild PMS, 31.5% had moderate PMS, 8.3% had strong PMS, and 13.3% had no symptoms. Anxiety and irritability were the most observed symptoms. The mean body mass index (BMI) of the participants was within the normal range (21.76 ± 4.81 kg/m2); however, body fat percentage was above the normal range (33.95% ± 4.89%). PMS severity was significantly correlated with body fat percentage and BMI. Nutrient intake was significantly lower than the recommended dietary allowance (RDA), but dietary fat consumption was higher than the RDA. Protein intake was higher in participants with mild PMS than those with moderate and severe PMS (p<0.05). An inverse association between oilseed consumption and PMS was observed.

Conclusion: PMS was associated with anthropometric parameters, nutrient intake, and dietary preference. PMS showed correlation with the intake of calorie-rich foods, sweets, and fried salted snacks, whereas consumption of oilseeds alleviated its incidence.

RevDate: 2022-05-13

Chen W, Ma J, Jiang Y, et al (2022)

Selective Maternal Seeding and Rearing Environment From Birth to Weaning Shape the Developing Piglet Gut Microbiome.

Frontiers in microbiology, 13:795101.

The acquisition and development of the mammalian microbiome early in life are critical to establish a healthy host-microbiome symbiosis. Despite recent advances in understanding microbial sources in infants, the relative contribution of various microbial sources to the colonization of the gut microbiota in pigs remains unclear. Here, we longitudinally sampled the microbiota of 20 sow-piglet pairs (three piglets per sow) reared under identical conditions from multiple body sites and the surrounding weaning environment from birth to 28 days postpartum (1,119 samples in total). Source-tracking analysis revealed that the contribution of various microbial sources to the piglet gut microbiome gradually changed over time. The neonatal microbiota was initially sparsely populated, and the predominant contribution was from the maternal vaginal microbiota that increased gradually from 69.0% at day 0 to 89.3% at day 3 and dropped to 0.28% at day 28. As the piglets aged, the major microbial community patterns were most strongly associated with the sow feces and slatted floor, with contributions increasing from 0.52 and 9.6% at day 0 to 62.1 and 33.8% at day 28, respectively. The intestinal microbial diversity, composition, and function significantly changed as the piglets aged, and 30 age-discriminatory bacterial taxa were identified with distinctive time-dependent shifts in their relative abundance, which likely reflected the effect of the maternal and environmental microbial sources on the selection and adaptation of the piglet gut microbiota. Overall, these data demonstrate that the vaginal microbiota is the primary source of the gut microbiota in piglets within 3 days after birth and are gradually replaced by the sow fecal and slatted floor microbiota over time. These findings may offer novel strategies to promote the establishment of exogenous symbiotic microbes to improve piglet gut health.

RevDate: 2022-05-13

Atala C, Acuña-Rodríguez IS, Torres-Díaz C, et al (2022)

Fungal endophytes improve the performance of host plants but do not eliminate the growth/defence trade-off.

RevDate: 2022-05-13

Moriyama M, Hayashi T, T Fukatsu (2022)

A mucin protein predominantly expressed in the female-specific symbiotic organ of the stinkbug Plautia stali.

Scientific reports, 12(1):7782.

Diverse insects are obligatorily associated with microbial symbionts, wherein the host often develops special symbiotic organs and vertically transmits the symbiont to the next generation. What molecular factors underpin the host-symbiont relationship is of great interest but poorly understood. Here we report a novel protein preferentially produced in a female-specific symbiotic organ of the stinkbug Plautia stali, whose posterior midgut develops numerous crypts to host a Pantoea-allied bacterial mutualist. In adult females, several posteriormost crypts are conspicuously enlarged, presumably specialized for vertical symbiont transmission. We detected conspicuous protein bands specific to the female's swollen crypts by gel electrophoresis, and identified them as representing a novel mucin-like glycoprotein. Histological inspections confirmed that the mucin protein is localized to the female's swollen crypts, coexisting with a substantial population of the symbiotic bacteria, and excreted from the swollen crypts to the midgut main tract together with the symbiotic bacteria. Using RNA interference, we successfully suppressed production of the mucin protein in adult females of P. stali. However, although the mucin protein was depleted, the symbiont population persisted in the swollen crypts, and vertical symbiont transmission to the next generation occurred. Possible biological roles and evolutionary trajectory of the symbiosis-related mucin protein are discussed.

RevDate: 2022-05-11

Merlin BL, Moraes GJ, FL Cônsoli (2022)

The Microbiota of a Mite Prey-Predator System on Different Host Plants Are Characterized by Dysbiosis and Potential Functional Redundancy.

Microbial ecology [Epub ahead of print].

Microbiota has diverse roles in the life cycles of their hosts, affecting their growth, development, behavior, and reproduction. Changes in physiological conditions of the host can also impact the assemblage of host-associated microorganisms. However, little is known of the effects of host plant-prey-predatory mite interactions on mite microbiota. We compared the microbial communities of eggs and adult females of the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and of adult females of the predatory mite Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) on four different host plants (cotton, maize, pinto bean, and tomato) by metabarcoding sequencing of the V3-V4 region of the 16S ribosomal RNA gene (16S rRNA), using the Illumina MiSeq platform. Only the egg microbiota of T. urticae was affected by the host plant. The microbiota of the predatory mite N. californicus was very different from that of its prey, and the predator microbiota was unaffected by the different host plant-prey systems tested. Only the microbiota of the eggs of T. urticae carried Serratia as a high fidelity-biomarker, but their low abundance in T. urticae adult females suggests that the association between Serratia and T. urticae is accidental. Biomarker bacteria were also detected in the microbiota of adult females of T. urticae and N. californicus, with different biomarkers in each host plant species. The microbiota associated with eggs and adult females of T. urticae and adult females of N. californicus differed in their functional potential contributions to the host mite.

RevDate: 2022-05-11

Khan A, Wadood SF, Chen M, et al (2022)

Effector-triggered inhibition of nodulation: a rhizobial effector protease targets soybean kinase GmPBS1-1.

Plant physiology pii:6584019 [Epub ahead of print].

Type III protein secretion systems of nitrogen-fixing rhizobia deliver effector proteins into leguminous host cells to promote or inhibit the nodule symbiosis. However, mechanisms underlying effector-triggered inhibition of nodulation remain largely unknown. Nodulation outer protein T (NopT) of Sinorhizobium sp. NGR234 is an effector protease related to the Pseudomonas effector AvrPphB (Avirulence protein Pseudomonas phaseolicola B). Here, we constructed NGR234 mutants producing different NopT variants and found that protease activity of NopT negatively affects nodulation of smooth crotalaria (Crotalaria pallida). NopT variants lacking residues required for autocleavage and subsequent lipidation showed reduced symbiotic effects and were not targeted to the plasma membrane. We further noticed that Sinorhizobium fredii strains possess a mutated nopT gene. S. fredii USDA257 expressing nopT of NGR234 induced considerably fewer nodules in soybean (Glycine max) cv. Nenfeng 15 but not in other cultivars. Effector perception was further examined in NopT-expressing leaves of Arabidopsis (Arabidopsis thaliana) and found to be dependent on the target protein AtPBS1 (Arabidopsis AvrPphB susceptible 1) and the associated resistance protein AtRPS5 (Arabidopsis Resistance to Pseudomonas Syringae 5). Experiments with Nicotiana benthamiana plants indicated that the soybean homolog GmPBS1-1 associated with AtRPS5 can perceive NopT. Further analysis showed that NopT cleaves AtPBS1 and GmPBS1-1 and thus can activate these target proteins. Insertion of a DKM motif at the cleavage site of GmPBS1-1 resulted in increased proteolysis. Nodulation tests with soybeans expressing an autoactive GmPBS1-1 variant indicated that activation of a GmPBS1-1-mediated resistance pathway impairs nodule formation in cv. Nenfeng 15. Our findings suggest that legumes face an evolutionary dilemma of either developing effector-triggered immunity against pathogenic bacteria or establishing symbiosis with suboptimally adapted rhizobia producing pathogen-like effectors.

RevDate: 2022-05-11

Mucci NC, Jones KA, Cao M, et al (2022)

Apex Predator Nematodes and Meso-Predator Bacteria Consume Their Basal Insect Prey through Discrete Stages of Chemical Transformations.

mSystems [Epub ahead of print].

Microbial symbiosis drives physiological processes of higher-order systems, including the acquisition and consumption of nutrients that support symbiotic partner reproduction. Metabolic analytics provide new avenues to examine how chemical ecology, or the conversion of existing biomass to new forms, changes over a symbiotic life cycle. We applied these approaches to the nematode Steinernema carpocapsae, its mutualist bacterium, Xenorhabdus nematophila, and the insects they infect. The nematode-bacterium pair infects, kills, and reproduces in an insect until nutrients are depleted. To understand the conversion of insect biomass over time into either nematode or bacterium biomass, we integrated information from trophic, metabolomic, and gene regulation analyses. Trophic analysis established bacteria as meso-predators and primary insect consumers. Nematodes hold a trophic position of 4.6, indicative of an apex predator, consuming bacteria and likely other nematodes. Metabolic changes associated with Galleria mellonella insect bioconversion were assessed using multivariate statistical analyses of metabolomics data sets derived from sampling over an infection time course. Statistically significant, discrete phases were detected, indicating the insect chemical environment changes reproducibly during bioconversion. A novel hierarchical clustering method was designed to probe molecular abundance fluctuation patterns over time, revealing distinct metabolite clusters that exhibit similar abundance shifts across the time course. Composite data suggest bacterial tryptophan and nematode kynurenine pathways are coordinated for reciprocal exchange of tryptophan and NAD+ and for synthesis of intermediates that can have complex effects on bacterial phenotypes and nematode behaviors. Our analysis of pathways and metabolites reveals the chemistry underlying the recycling of organic material during carnivory. IMPORTANCE The processes by which organic life is consumed and reborn in a complex ecosystem were investigated through a multiomics approach applied to the tripartite Xenorhabdus bacterium-Steinernema nematode-Galleria insect symbiosis. Trophic analyses demonstrate the primary consumers of the insect are the bacteria, and the nematode in turn consumes the bacteria. This suggests the Steinernema-Xenorhabdus mutualism is a form of agriculture in which the nematode cultivates the bacterial food sources by inoculating them into insect hosts. Metabolomics analysis revealed a shift in biological material throughout progression of the life cycle: active infection, insect death, and conversion of cadaver tissues into bacterial biomass and nematode tissue. We show that each phase of the life cycle is metabolically distinct, with significant differences including those in the tricarboxylic acid cycle and amino acid pathways. Our findings demonstrate that symbiotic life cycles can be defined by reproducible stage-specific chemical signatures, enhancing our broad understanding of metabolic processes that underpin a three-way symbiosis.

RevDate: 2022-05-11

Pfab F, Brown AL, Detmer AR, et al (2022)

Timescale separation and models of symbiosis: state space reduction, multiple attractors and initialization.

Conservation physiology, 10(1):coac026 pii:coac026.

Dynamic Energy Budget models relate whole organism processes such as growth, reproduction and mortality to suborganismal metabolic processes. Much of their potential derives from extensions of the formalism to describe the exchange of metabolic products between organisms or organs within a single organism, for example the mutualism between corals and their symbionts. Without model simplification, such models are at risk of becoming parameter-rich and hence impractical. One natural simplification is to assume that some metabolic processes act on 'fast' timescales relative to others. A common strategy for formulating such models is to assume that 'fast' processes equilibrate immediately, while 'slow' processes are described by ordinary differential equations. This strategy can bring a subtlety with it. What if there are multiple, interdependent fast processes that have multiple equilibria, so that additional information is needed to unambiguously specify the model dynamics? This situation can easily arise in contexts where an organism or community can persist in a 'healthy' or an 'unhealthy' state with abrupt transitions between states possible. To approach this issue, we offer the following: (a) a method to unambiguously complete implicitly defined models by adding hypothetical 'fast' state variables; (b) an approach for minimizing the number of additional state variables in such models, which can simplify the numerical analysis and give insights into the model dynamics; and (c) some implications of the new approach that are of practical importance for model dynamics, e.g. on the bistability of flux dynamics and the effect of different initialization choices on model outcomes. To demonstrate those principles, we use a simplified model for root-shoot dynamics of plants and a related model for the interactions between corals and endosymbiotic algae that describes coral bleaching and recovery.

RevDate: 2022-05-11
CmpDate: 2022-05-11

Zakeri Z, Junne S, Jäger F, et al (2022)

Lichen cell factories: methods for the isolation of photobiont and mycobiont partners for defined pure and co-cultivation.

Microbial cell factories, 21(1):80.

BACKGROUND: Due to their huge biodiversity and the capability to produce a wide range of secondary metabolites, lichens have a great potential in biotechnological applications. They have, however, hardly been used as cell factories to date, as it is considered to be difficult and laborious to cultivate lichen partners in pure or co-culture in the laboratory. The various methods used to isolate lichen fungi, based on either the ascospores, the conidia, or the thallus, have so far not been compared or critically examined. Therefore, here we systematically investigate and compare the known methods and two new methods to identify the most suitable technology for isolation of fungi from lichens.

RESULTS: Within this study six lichen fungi species were isolated and propagated as pure cultures. All of them formed colonies within one month. In case of lichens with ascocarps the spore discharge was the most suitable method. Spores were already discharged within 2 days and germinated within only four days and the contamination rate was low. Otherwise, the soredia and thallus method without homogenization, as described in this work, are also well suited to obtain pure fungal cultures. For the isolation of algae, we were also successful with the thallus method without homogenization.

CONCLUSION: With the methods described here and the proposed strategic approach, we believe that a large proportion of the lichen fungi can be cultivated within a reasonable time and effort. Based on this, methods of controlled cultivation and co-cultivation must now be developed in order to use the potential of lichens with regard to their secondary metabolites, but also for other applications.

RevDate: 2022-05-11
CmpDate: 2022-05-11

de Raad J, Päckert M, Irestedt M, et al (2022)

Speciation and population divergence in a mutualistic seed dispersing bird.

Communications biology, 5(1):429.

Bird-mediated seed dispersal is crucial for the regeneration and viability of ecosystems, often resulting in complex mutualistic species networks. Yet, how this mutualism drives the evolution of seed dispersing birds is still poorly understood. In the present study we combine whole genome re-sequencing analyses and morphometric data to assess the evolutionary processes that shaped the diversification of the Eurasian nutcracker (Nucifraga), a seed disperser known for its mutualism with pines (Pinus). Our results show that the divergence and phylogeographic patterns of nutcrackers resemble those of other non-mutualistic passerine birds and suggest that their early diversification was shaped by similar biogeographic and climatic processes. The limited variation in foraging traits indicates that local adaptation to pines likely played a minor role. Our study shows that close mutualistic relationships between bird and plant species might not necessarily act as a primary driver of evolution and diversification in resource-specialized birds.

RevDate: 2022-05-11
CmpDate: 2022-05-11

Koltz AM, Civitello DJ, Becker DJ, et al (2022)

Sublethal effects of parasitism on ruminants can have cascading consequences for ecosystems.

Proceedings of the National Academy of Sciences of the United States of America, 119(20):e2117381119.

SignificanceWe found that pervasive parasitic infections reduce herbivory rates and can trigger trophic cascades. Lethal parasites clearly have cascading impacts on ecosystems, but whether common sublethal infections have similar effects is largely unknown. Using a mathematical model, we probed how parasites that reduce host survival, fecundity, or feeding rates can indirectly alter producer biomass in a helminth-ruminant system. We found that both lethal and sublethal infections triggered trophic cascades by altering the biomass of ruminant herbivore hosts and their resources. However, a global meta-analysis revealed that helminths tend to have pervasive sublethal effects on free-living ruminants, including by reducing host feeding rates. Our findings suggest there are widespread, but overlooked, ecological consequences of sublethal infections in natural ecosystems.

RevDate: 2022-05-11
CmpDate: 2022-05-11

Zaw M, Rathjen JR, Zhou Y, et al (2022)

Rhizobial diversity is associated with inoculation history at a two-continent scale.

FEMS microbiology ecology, 98(5):.

A total of 120 Mesorhizobium strains collected from the central dry zone of Myanmar were analyzed in a pot experiment to evaluate nodulation and symbiotic effectiveness (SE%) in chickpea plants. Phylogenetic analyses revealed all strains belonged to the genus Mesorhizobium according to 16-23S rDNA IGS and the majority of chickpea nodulating rhizobia in Myanmar soils were most closely related to M. gobiense, M. muleiense, M. silamurunense, M. tamadayense and M. temperatum. Around two-thirds of the Myanmar strains (68%) were most closely related to Indian strain IC-2058 (CA-181), which is also most closely related to M. gobiense. There were no strains that were closely related to the cognate rhizobial species to nodulate chickpea: M. ciceri and M. mediterraneum. Strains with diverse 16S-23S rDNA IGS shared similar nodC and nifH gene sequences with chickpea symbionts. Detailed sequence analysis of nodC and nifH found that the strains in Myanmar were somewhat divergent from the group including M. ciceri and were more closely related to M. muleiense and IC-2058. A cross-continent analysis between strains isolated in Australia compared with Myanmar found that there was little overlap in species, where Australian soils were dominated with M. ciceri, M. temperatum and M. huakuii. The only co-occurring species found in both Myanmar and Australia were M. tamadayense and M. silumurunense. Continued inoculation with CC1192 may have reduced diversity of chickpea strains in Australian soils. Isolated strains in Australian and Myanmar had similar adaptive traits, which in some cases were also phylogenetically related. The genetic discrepancy between chickpea nodulating strains in Australia and Myanmar is not only due to inoculation history but to adaptation to soil conditions and crop management over a long period, and there has been virtually no loss of symbiotic efficiency over this time in strains isolated from soils in Myanmar.

RevDate: 2022-05-11
CmpDate: 2022-05-11

Adjei JA, Aserse AA, Yli-Halla M, et al (2022)

Phylogenetically diverse Bradyrhizobium genospecies nodulate Bambara groundnut (Vigna subterranea L. Verdc) and soybean (Glycine max L. Merril) in the northern savanna zones of Ghana.

FEMS microbiology ecology, 98(5):.

A total of 102 bacterial strains isolated from nodules of three Bambara groundnut and one soybean cultivars grown in nineteen soil samples collected from northern Ghana were characterized using multilocus gene sequence analysis. Based on a concatenated sequence analysis (glnII-rpoB-recA-gyrB-atpD-dnaK), 54 representative strains were distributed in 12 distinct lineages, many of which were placed mainly in the Bradyrhizobium japonicum and Bradyrhizobium elkanii supergroups. Twenty-four of the 54 representative strains belonged to seven putative novel species, while 30 were conspecific with four recognized Bradyrhizobium species. The nodA phylogeny placed all the representative strains in the cosmopolitan nodA clade III. The strains were further separated in seven nodA subclusters with reference strains mainly of African origin. The nifH phylogeny was somewhat congruent with the nodA phylogeny, but both symbiotic genes were mostly incongruent with the core housekeeping gene phylogeny indicating that the strains acquired their symbiotic genes horizontally from distantly related Bradyrhizobium species. Using redundancy analysis, the distribution of genospecies was found to be influenced by the edaphic factors of the respective sampling sites. In general, these results mainly underscore the high genetic diversity of Bambara groundnut-nodulating bradyrhizobia in Ghanaian soils and suggest a possible vast resource of adapted inoculant strains.

RevDate: 2022-05-10

Chen KH, J Nelson (2022)

A Scoping Review of Bryophyte Microbiota: Diverse Microbial Communities in Small Plant Packages.

Journal of experimental botany pii:6583427 [Epub ahead of print].

Plant health depends not only on the condition of the plant itself but also on its diverse community of microbes, or microbiota. Just like the better-studied angiosperms, bryophytes (mosses, liverworts, and hornworts) harbor diverse communities of bacteria, archaea, fungi, and other microbial eukaryotes. Bryophytes are increasingly recognized as important model systems for understanding plant evolution, development, physiology, and symbiotic interactions. Much of the work on bryophyte microbiota in the past focused on specific symbiont types for each bryophyte group, but more recent studies have started to expand the view. Therefore, this review integrates studies of bryophyte microbes from both scopes to provide a holistic view of the existing research for each bryophyte group and on key themes. The systematic search also reveals the taxonomic and geographic biases in this field, including a severe underrepresentation of the tropics, very few studies on viruses or eukaryotic microbes beyond fungi, and overrepresentation of mycorrhizal fungi studies in liverworts. Such gaps may lead to errors in conclusions about evolutionary patterns in symbiosis. This analysis points to a wealth of future research directions that promise to reveal how the distinct life cycles and physiology of bryophytes interact with their microbiota.

RevDate: 2022-05-10

Kumar H, Kumar N, N Kaur (2022)

Non-Standardized Terminology in Healthcare: Shortcomings and Subsequent Rectifications [Letter].

Infection and drug resistance, 15:2369-2370 pii:370670.

RevDate: 2022-05-09

Zhang H, Mascher M, Abbo S, et al (2022)

Advancing Grain Legumes Domestication and Evolution Studies with Genomics.

Plant & cell physiology pii:6582909 [Epub ahead of print].

Grain legumes were domesticated in parallel with cereals in several regions of the world and formed the economic basis of early farming cultures. Since then, legumes have played a vital role in human and animal diets and in fostering agrobiodiversity. Increasing grain legume cultivation will be crucial to safeguard nutritional security and the resilience of agricultural ecosystems across the globe. A better understanding of the molecular underpinnings of domestication and crop evolution of grain legumes may be translated into practical approaches in modern breeding programs to stabilize yield, which is threatened by evolving pathogens and changing climates. During recent decades, domestication research in all crops has greatly benefitted from the fast progress in genomics technologies. Yet still, many questions surrounding the domestication and diversification of legumes remain unanswered. In this review, we assess the potential of genomic approaches in grain legume research. We describe the centers of origin and the crucial domestication traits of grain legumes. In addition, we survey the effect of domestication on both above-ground and below-ground traits that have economic importance. Finally, we discuss open questions in grain legume domestication and diversification and outline how to bridge the gap between the preservation of historic crop diversity and their utilization in modern plant breeding.

RevDate: 2022-05-09

Pang L, Khan F, Dunterman M, et al (2022)

Pharmacological targeting of the tumor-immune symbiosis in glioblastoma.

Trends in pharmacological sciences pii:S0165-6147(22)00082-7 [Epub ahead of print].

Glioblastoma (GBM) is the most common and highly lethal form of primary brain tumor in adults. The median survival of GBM patients is approximately 14-16 months despite multimodal therapies. Emerging evidence has substantiated the critical role of symbiotic interactions between GBM cells and noncancerous immune cells (e.g., myeloid cells and T cells) in regulating tumor progression and therapy resistance. Approaches to target the tumor-immune symbiosis have emerged as a promising therapeutic strategy for GBM. Here, we review the recent developments for pharmacological targeting of the GBM-immune symbiosis and highlight the role of such strategies to improve the effectiveness of immunotherapies in GBM.

RevDate: 2022-05-10
CmpDate: 2022-05-10

Fujita R (2021)

[Osugoroshi virus, a male-killer virus].

Uirusu, 71(1):63-70.

In insects, sex ratio bias is sometimes introduced by feminization, parthenogenesis, cytoplasmic incompatibility, or male-killing. Some intracellular bacteria such as Wolbachia or Spiroplasma has been known as male-killing agents. Here I introduce an example of non-bacterial male-killing agent, Osugoroshi virus found in oriental tea tortrix.

RevDate: 2022-05-10
CmpDate: 2022-05-10

Anonymous (2022)

David J. Lynn.

Cell reports. Medicine, 3(4):100611.

In this Q&A we speak with David Lynn, an EMBL Australia Group Leader at the South Australian Health and Medical Research Institute and a professor at Flinders University, about his research applying systems immunology approaches to better understand how pathogen and commensal microbes regulate our immune system in different contexts.

RevDate: 2022-05-10
CmpDate: 2022-05-10

Foster-Nyarko E, MJ Pallen (2022)

The microbial ecology of Escherichia coli in the vertebrate gut.

FEMS microbiology reviews, 46(3):.

Escherichia coli has a rich history as biology's 'rock star', driving advances across many fields. In the wild, E. coli resides innocuously in the gut of humans and animals but is also a versatile pathogen commonly associated with intestinal and extraintestinal infections and antimicrobial resistance-including large foodborne outbreaks such as the one that swept across Europe in 2011, killing 54 individuals and causing approximately 4000 infections and 900 cases of haemolytic uraemic syndrome. Given that most E. coli are harmless gut colonizers, an important ecological question plaguing microbiologists is what makes E. coli an occasionally devastating pathogen? To address this question requires an enhanced understanding of the ecology of the organism as a commensal. Here, we review how our knowledge of the ecology and within-host diversity of this organism in the vertebrate gut has progressed in the 137 years since E. coli was first described. We also review current approaches to the study of within-host bacterial diversity. In closing, we discuss some of the outstanding questions yet to be addressed and prospects for future research.

RevDate: 2022-05-10
CmpDate: 2022-05-10

Alonso AC, Stein M, Matías Hisgen C, et al (2022)

Abiotic factors affecting the prevalence of Wolbachia (Rickettsiaceae) in immature Aedes albopictus (Skuse) (Culicidae).

Journal of invertebrate pathology, 189:107730.

Wolbachia is a genus of gram-negative endosymbiotic bacterium of maternal transmission, located mainly in the gonads of arthropods, including mosquitoes such as Aedes albopictus. The current distribution of Ae. albopictus in Argentina is restricted to the subtropical northeastern region of the country. Here, we studied the seasonal prevalence of Wolbachia detected in Ae. albopictus larvae and the relationship between the abiotic factors of the larval microhabitat and the infection status, in Eldorado city, Misiones province, subtropical region. The prevalence of Wolbachia infection found was 76.89% (n = 312). From the total samples examined, 52.80% (n = 214) showed double infection with the wAlbA/wAlbB strains, 23.84% (n = 97) infection only with wAlbB, and 0.25% (n = 1) only with wAlbA. The prevalence of double infection did not present statistically significant differences between the sites studied. For single infection, the lowest prevalence value of the wAlbB strain (13.33%) was found in the natural park, whereas the highest was found in the family dwellings and cemeteries. Tire repair shops showed an intermediate value. The wAlbA single infection was identified once. Our results also showed an association between temperature and slightly turbid waters with exposure to the sun in the larval habitats and the probability of infection by Wolbachia.


ESP Quick Facts

ESP Origins

In the early 1990's, Robert Robbins was a faculty member at Johns Hopkins, where he directed the informatics core of GDB — the human gene-mapping database of the international human genome project. To share papers with colleagues around the world, he set up a small paper-sharing section on his personal web page. This small project evolved into The Electronic Scholarly Publishing Project.

ESP Support

In 1995, Robbins became the VP/IT of the Fred Hutchinson Cancer Research Center in Seattle, WA. Soon after arriving in Seattle, Robbins secured funding, through the ELSI component of the US Human Genome Project, to create the original ESP.ORG web site, with the formal goal of providing free, world-wide access to the literature of classical genetics.

ESP Rationale

Although the methods of molecular biology can seem almost magical to the uninitiated, the original techniques of classical genetics are readily appreciated by one and all: cross individuals that differ in some inherited trait, collect all of the progeny, score their attributes, and propose mechanisms to explain the patterns of inheritance observed.

ESP Goal

In reading the early works of classical genetics, one is drawn, almost inexorably, into ever more complex models, until molecular explanations begin to seem both necessary and natural. At that point, the tools for understanding genome research are at hand. Assisting readers reach this point was the original goal of The Electronic Scholarly Publishing Project.

ESP Usage

Usage of the site grew rapidly and has remained high. Faculty began to use the site for their assigned readings. Other on-line publishers, ranging from The New York Times to Nature referenced ESP materials in their own publications. Nobel laureates (e.g., Joshua Lederberg) regularly used the site and even wrote to suggest changes and improvements.

ESP Content

When the site began, no journals were making their early content available in digital format. As a result, ESP was obliged to digitize classic literature before it could be made available. For many important papers — such as Mendel's original paper or the first genetic map — ESP had to produce entirely new typeset versions of the works, if they were to be available in a high-quality format.

ESP Help

Early support from the DOE component of the Human Genome Project was critically important for getting the ESP project on a firm foundation. Since that funding ended (nearly 20 years ago), the project has been operated as a purely volunteer effort. Anyone wishing to assist in these efforts should send an email to Robbins.

ESP Plans

With the development of methods for adding typeset side notes to PDF files, the ESP project now plans to add annotated versions of some classical papers to its holdings. We also plan to add new reference and pedagogical material. We have already started providing regularly updated, comprehensive bibliographies to the ESP.ORG site.

Electronic Scholarly Publishing
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Bellingham, WA 98226

E-mail: RJR8222 @

Papers in Classical Genetics

The ESP began as an effort to share a handful of key papers from the early days of classical genetics. Now the collection has grown to include hundreds of papers, in full-text format.

Digital Books

Along with papers on classical genetics, ESP offers a collection of full-text digital books, including many works by Darwin (and even a collection of poetry — Chicago Poems by Carl Sandburg).


ESP now offers a much improved and expanded collection of timelines, designed to give the user choice over subject matter and dates.


Biographical information about many key scientists.

Selected Bibliographies

Bibliographies on several topics of potential interest to the ESP community are now being automatically maintained and generated on the ESP site.

ESP Picks from Around the Web (updated 07 JUL 2018 )