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1.
Adv Exp Med Biol ; 1131: 827-855, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31646536

RESUMO

Calcium (Ca2+) is a universal signaling ion, whose major informational role shaped the evolution of signaling pathways, enabling cellular communications and responsiveness to both the intracellular and extracellular environments. Elaborate Ca2+ regulatory networks have been well characterized in eukaryotic cells, where Ca2+ regulates a number of essential cellular processes, ranging from cell division, transport and motility, to apoptosis and pathogenesis. However, in bacteria, the knowledge on Ca2+ signaling is still fragmentary. This is complicated by the large variability of environments that bacteria inhabit with diverse levels of Ca2+. Yet another complication arises when bacterial pathogens invade a host and become exposed to different levels of Ca2+ that (1) are tightly regulated by the host, (2) control host defenses including immune responses to bacterial infections, and (3) become impaired during diseases. The invading pathogens evolved to recognize and respond to the host Ca2+, triggering the molecular mechanisms of adhesion, biofilm formation, host cellular damage, and host-defense resistance, processes enabling the development of persistent infections. In this review, we discuss: (1) Ca2+ as a determinant of a host environment for invading bacterial pathogens, (2) the role of Ca2+ in regulating main events of host colonization and bacterial virulence, and (3) the molecular mechanisms of Ca2+ signaling in bacterial pathogens.


Assuntos
Bactérias , Cálcio , Interações entre Hospedeiro e Microrganismos , Virulência , Bactérias/patogenicidade , Infecções Bacterianas/microbiologia , Infecções Bacterianas/fisiopatologia , Cálcio/metabolismo , Humanos , Virulência/fisiologia
2.
Braz Oral Res ; 33(suppl 1): e066, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31576950

RESUMO

Considering the absence of predictable and effective therapeutic interventions for the treatment of peri-implantitis, scientific evidence concerning the host response profile around dental implants could be important for providing in the future a wider preventive and/or therapeutic window for this peri-implant lesion, indicating biomarkers that provide quantifiable measure of response to peri-implant therapy. Moreover, a better knowledge of pattern of host osteo-immunoinflammatory modulation in the presence of peri-implantitis could either benefit the early diagnostic of the disease or to cooperate to prognostic information related to the status of the peri-implant breakdown. Finally, new evidences concerning the host profile of modulators of inflammation and of osseous tissue metabolism around dental implants could explain the individual susceptibility for developing peri-implant lesions, identifying individuals or sites with increased risk for peri-implantitis. The focus of this chapter was, based on a systematically searched and critically reviewed literature, summarizing the existing knowledge in the scientific research concerning the host osteo-immunoinflammatory response to the microbiological challenge related to periimplantitis.


Assuntos
Implantes Dentários , Peri-Implantite/imunologia , Biomarcadores , Reabsorção Óssea/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Interleucinas/imunologia , Metaloproteinases da Matriz/imunologia , Peri-Implantite/microbiologia
3.
Virol J ; 16(1): 90, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319897

RESUMO

BACKGROUND: Nelson Bay orthoreovirus (NBV) was first isolated over 40 years ago from a fruit bat in Australia. Normally, NBV does not cause human diseases, but recently several NBV strains have been associated with human respiratory tract infections, thus attracting clinical attention. Autophagy, an evolutionarily conserved process in eukaryotic cells, degrades intracellular substrates, participates in multiple physiological processes, and maintains cellular homeostasis. In addition, autophagy is intimately involved in viral infection. METHODS: A new strain of NBV, isolated from a patient with a respiratory tract infection who returned to Japan from Bali, Indonesia, in 2007, was used in this study. NBV was rescued using a reverse genetics system involving cotransfection of BHK cells with 11 plasmids (pT7-L1 MB, pT7-L2 MB, pT7-L3 MB, pT7-M1 MB, pT7-M2 MB, pT7-M3 MB, pT7-S1 MB, pT7-S2 MB, pT7-S3 MB, pT7-S4 MB, and pcDNA3.1-T7), yielding NBV-MB. Recovered viruses were confirmed by immunofluorescence. The effect of NBV-MB on autophagy was evaluated by measuring the LC3-I/II proteins by immunoblot analysis after infection of BHK cells. Furthermore, after treatment with rapamycin (RAPA), 3-methyladenine (3-MA), chloroquine (CQ), or plasmid (GFP-LC3) transfection, the changes in expression of the LC3 gene and the amount of LC3-I/II protein were examined. In addition, variations in viral titer were assayed after treatment of BHK cells with drugs or after transfection with plasmids pCAGM3 and pCAGS3, which encode virus nonstructural proteins µNS and σNS, respectively. RESULTS: NBV-MB infection induced autophagy in host cells; however, the level of induction was dependent on viral replication. Induction of autophagy increased viral replication. By contrast, inhibiting autophagy suppressed NBV replication, albeit not significantly. The NBV-MB nonstructural protein µNS was involved in the induction of autophagy with viral infection. CONCLUSIONS: NBV-MB infection triggered autophagy. Also, the NBV nonstructural protein µNS may contribute to augmentation of autophagy upon viral infection.


Assuntos
Autofagia , Interações entre Hospedeiro e Microrganismos , Orthoreovirus/fisiologia , Replicação Viral , Linhagem Celular , Células HEK293 , Humanos , Infecções por Reoviridae/virologia , Genética Reversa , Carga Viral , Proteínas Virais/genética
4.
Vet Microbiol ; 235: 127-135, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282370

RESUMO

Lawsonia intracellularis is an obligate intracellular Gram-negative bacterium that has been identified as the etiological agent of the contagious disease proliferative enteropathy (PE) in a wide range of animals, mainly pigs. The genome sequence of L. intracellularis indicates that this bacterium possess a type III secretion system (T3SS), which may assist the bacterium during cell invasion and host innate immune system evasion and could be a mechanism for inducing cellular proliferation. However, the effectors secreted by the T3SS (T3Es) of L. intracellularis have not been reported. T3Es often target conserved eukaryotic cellular processes, and yeast is an established and robust model system in which to reveal their function. By screening the growth inhibition of an ordered array of Saccharomyces cerevisiae strains expressing the hypothetical genes of L. intracellularis, LI1035 was identified as the first putative effector that inhibits yeast growth. The LI1035-induced growth inhibition was rescued in two of the 14 mitogen-activated protein kinase (MAPK) yeast haploid deletion strains, suggesting that LI1035 interacts with the components of the MAPK pathway in yeast. Phosphorylation assays confirmed that LI1035 inhibits MAPK signaling cascades in yeast and mammalian cells. Actin staining assays revealed that LI1035 regulates actin organization in yeast and mammalian cells. Taken together, these results indicate that LI1035 alters MAPK pathway activity and regulates actin organization in the host. These findings may contribute to the understanding the pathogenesis of L. intracellularis and support the use of yeast as a heterologous system for the functional analysis of pathogen-specific gene products in the laboratory.


Assuntos
Actinas/metabolismo , Proteínas de Bactérias/metabolismo , Lawsonia (Bactéria)/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Transdução de Sinais , Animais , Proteínas de Bactérias/genética , Proliferação de Células , Interações entre Hospedeiro e Microrganismos , Lawsonia (Bactéria)/genética , Fosforilação , Saccharomyces cerevisiae/genética , Sorbitol/farmacologia , Suínos , Temperatura Ambiente
5.
Microb Pathog ; 135: 103610, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31288065

RESUMO

The WRKY transcription factors (TFs) family constitutes a major group of TFs in spermatophytes. Different studies have endorsed the considerable biological roles performed by WRKY TFs in plant growth, biotic and abiotic stress responses. Genomic and transcriptomic profiling facilitate us in understanding the WRKY genes in various plants and reveal how WRKY TFs perform their action in response to different plant stresses. WRKY TFs actively take part in metabolism including carbohydrate synthesis, senescence, and secondary metabolites production. Molecular organization of WRKY TFs in plants highlight most predicted outcome of multiple responses simultaneously. Repression and activation related to W-box and other such elements is controlled at transcriptional, translational and domain level. WRKY TFs are becoming more important in crop improvement because of their binding with downstream elements. Additionally, WRKY proteins intermingle with various other TFs for modulating plant immunity. However, WRKY TFs self-regulation and crosstalk between different signaling pathways using WRKY TFs still need extensive investigations. In this review, we focused characteristics of WRKY TFs in Capsicum annum and related research advancement on their functional involvement in plant responses to the challenges of high temperature stress and pathogens infection. We summarized information about Capsicum annum WRKY TFs on the basis of their functions, their target genes and signaling pathways. Moreover, the mechanisms for synergistic responses to various biotic and abiotic stresses, WRKY target genes and other TFs as well will be of more interest with increments in existing information.


Assuntos
Capsicum/genética , Capsicum/imunologia , Imunidade Inata , Imunidade Vegetal/genética , Imunidade Vegetal/imunologia , Estresse Fisiológico/genética , Estresse Fisiológico/imunologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Umidade , Estágios do Ciclo de Vida/fisiologia , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Metabolismo Secundário , Transdução de Sinais , Temperatura Ambiente , Fatores de Transcrição
6.
Nat Commun ; 10(1): 3048, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296855

RESUMO

Bacteriophages typically hijack the host bacterial transcriptional machinery to regulate their own gene expression and that of the host bacteria. The structural basis for bacteriophage protein-mediated transcription regulation-in particular transcription antitermination-is largely unknown. Here we report the 3.4 Å and 4.0 Å cryo-EM structures of two bacterial transcription elongation complexes (P7-NusA-TEC and P7-TEC) comprising the bacteriophage protein P7, a master host-transcription regulator encoded by bacteriophage Xp10 of the rice pathogen Xanthomonas oryzae pv. Oryzae (Xoo) and discuss the mechanisms by which P7 modulates the host bacterial RNAP. The structures together with biochemical evidence demonstrate that P7 prevents transcription termination by plugging up the RNAP RNA-exit channel and impeding RNA-hairpin formation at the intrinsic terminator. Moreover, P7 inhibits transcription initiation by restraining RNAP-clamp motions. Our study reveals the structural basis for transcription antitermination by phage proteins and provides insights into bacterial transcription regulation.


Assuntos
Proteínas de Bactérias/metabolismo , Bacteriófagos/genética , Fatores de Elongação da Transcrição/metabolismo , Proteínas Virais/metabolismo , Xanthomonas/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/ultraestrutura , Microscopia Crioeletrônica , RNA Polimerases Dirigidas por DNA/isolamento & purificação , RNA Polimerases Dirigidas por DNA/metabolismo , RNA Polimerases Dirigidas por DNA/ultraestrutura , Regulação Bacteriana da Expressão Gênica , Regulação Viral da Expressão Gênica , Interações entre Hospedeiro e Microrganismos/genética , Oryza/microbiologia , Estrutura Secundária de Proteína , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Regiões Terminadoras Genéticas/genética , Transcrição Genética , Fatores de Elongação da Transcrição/isolamento & purificação , Fatores de Elongação da Transcrição/ultraestrutura , Proteínas Virais/isolamento & purificação , Proteínas Virais/ultraestrutura , Xanthomonas/virologia
7.
Nat Commun ; 10(1): 3092, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300639

RESUMO

The global decline of coral reefs heightens the need to understand how corals respond to changing environmental conditions. Corals are metaorganisms, so-called holobionts, and restructuring of the associated bacterial community has been suggested as a means of holobiont adaptation. However, the potential for restructuring of bacterial communities across coral species in different environments has not been systematically investigated. Here we show that bacterial community structure responds in a coral host-specific manner upon cross-transplantation between reef sites with differing levels of anthropogenic impact. The coral Acropora hemprichii harbors a highly flexible microbiome that differs between each level of anthropogenic impact to which the corals had been transplanted. In contrast, the microbiome of the coral Pocillopora verrucosa remains remarkably stable. Interestingly, upon cross-transplantation to unaffected sites, we find that microbiomes become indistinguishable from back-transplanted controls, suggesting the ability of microbiomes to recover. It remains unclear whether differences to associate with bacteria flexibly reflects different holobiont adaptation mechanisms to respond to environmental change.


Assuntos
Aclimatação/fisiologia , Antozoários/microbiologia , Antozoários/fisiologia , Translocação Bacteriana/fisiologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/fisiologia , Animais , Recifes de Corais , Simbiose
8.
J Chem Ecol ; 45(7): 610-625, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31281942

RESUMO

Plants use volatile organic compounds (VOCs) to cue natural enemies to their herbivore prey on plants. Simultaneously, herbivores utilize volatile cues to identify appropriate hosts. Despite extensive efforts to understand sources of variation in plant communication by VOCs, we lack an understanding of how ubiquitous belowground mutualists, such as arbuscular mycorrhizal fungi (AMF), influence plant VOC emissions. In a full factorial experiment, we subjected plants of two milkweed (Asclepias) species under three levels of AMF availability to damage by aphids (Aphis nerii). We then measured plant headspace volatiles and chemical defenses (cardenolides) and compared these to VOCs emitted and cardenolides produced by plants without herbivores. We found that AMF have plant species-specific effects on constitutive and aphid-induced VOC emissions. High AMF availability increased emissions of total VOCs, two green leaf volatiles (3-hexenyl acetate and hexyl acetate), and methyl salicylate in A. curassavica, but did not affect emissions in A. incarnata. In contrast, aphids consistently increased emissions of 6-methyl-5-hepten-2-one and benzeneacetaldehyde in both species, independent of AMF availability. Both high AMF availability and aphids alone suppressed emissions of individual terpenes. However, aphid damage on plants under high AMF availability increased, or did not affect, emissions of those terpenes. Lastly, aphid feeding suppressed cardenolide concentrations only in A. curassavica, and AMF did not affect cardenolides in either plant species. Our findings suggest that by altering milkweed VOC profiles, AMF may affect both herbivore performance and natural enemy attraction.


Assuntos
Afídeos/fisiologia , Asclepias/química , Micorrizas/fisiologia , Compostos Orgânicos Voláteis/análise , Animais , Asclepias/metabolismo , Asclepias/parasitologia , Cardenolídeos/análise , Cromatografia Gasosa-Espectrometria de Massas , Herbivoria , Interações entre Hospedeiro e Microrganismos , Interações Hospedeiro-Parasita , Folhas de Planta/química , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Análise de Componente Principal
9.
Ecotoxicol Environ Saf ; 180: 749-755, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31154199

RESUMO

The present study emphasizes on the antimicrobial susceptibility of different bacterial strains isolated from the external body surface of a commonly found zooplanktonic copepod (Heliodiaptomus viduus, Gurney, 1916) inhabiting both in fresh and brackish water bodies of Midnapore (West and East) Districts, West Bengal, India. Out of 62 bacterial isolated strains, 38 isolates were identified as Gram-positive while the remaining 24 isolates were found to be Gram-negative. Antimicrobial properties of all those bacterial strains were determined by Vitek 2 compact system using minimum inhibitory concentration (MIC) values. All isolated bacterial strains had exhibited differential susceptibilities against some selected antibiotics. Field Emission Scanning Electron Microscope (FE-SEM) analysis revealed the considerable association of bacteria on the cuticular body parts of the studied zooplankton. The outcomes of the present research are expected to enable health professionals in identifying two major problems -1) bacterial association with zooplankton which is so far mostly considered as a novel source of food for fish in aquatic ecosystems. 2) Selection of antibiotics as treatment measure because of the pathogenic effects of zooplankton associated bacteria on human being. This unattended arena of research is also supposed to evoke a new dimension not only because of bacteria-zooplankton interactions but also on undertaking of judicious strategies to find out proper ways and means to make the surface water suitable for the utilization by the common peoples (minimising bacterial contamination) in the context of human health and environmental safety.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Copépodes/microbiologia , Microbiologia da Água , Zooplâncton/microbiologia , Animais , Bactérias/classificação , Interações entre Hospedeiro e Microrganismos , Humanos , Índia , Testes de Sensibilidade Microbiana
10.
Vet J ; 249: 10-15, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31239159

RESUMO

There has been a marked increase in interest regarding complex microbial populations in recent years. The methodology used for microbial assessment has drastically changed over the last two decades and continues to advance at a rapid pace. Culture-based studies have been superseded by those based upon molecular methods, which have been largely used to discover new species and to better characterize complex communities, mainly driven by the advances in DNA sequencing, termed 'next generation sequencing'. These methodologies have allowed for a better understanding of the relationship between hosts and their microbiotas, which have important roles in health maintenance and in the pathophysiology of wide ranging conditions such as obesity, diabetes, allergic diseases and even behavioural changes. While most widely used in humans, these approaches are now commonly used in veterinary research, with increasing interest in direct clinical applications. As these methods provide novel insights that will constitute the basis for the development of new therapeutic and prevention strategies, and as commercial efforts to offer microbiota assessment as a clinical tool expand, it is essential for researchers and clinical veterinarians to understand and have the tools to be able to interpret research performed in this new fascinating field. The objective of this review is to describe some of the most common methods for characterization of microbial communities and to provide an overview of the basic concepts necessary for good interpretation of the research performed in this field.


Assuntos
Técnicas Bacteriológicas/veterinária , Microbiota , Animais , Bactérias/genética , DNA Bacteriano , Interações entre Hospedeiro e Microrganismos , Análise de Sequência de DNA/veterinária
11.
PLoS Comput Biol ; 15(5): e1007109, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31150382

RESUMO

Understanding the mechanisms that promote the assembly and maintenance of host-beneficial microbiomes is an open problem. Empirical evidence supports the idea that animal and plant hosts can combine 'private resources' with the ecological phenomenon known as 'community bistability' to favour some microbial strains over others. We briefly review evidence showing that hosts can: (i) protect the growth of beneficial strains in an isolated habitat, (ii) use antibiotics to suppress non-beneficial, competitor strains, and (iii) provide resources that only beneficial strains are able to translate into an increased rate of growth, reproduction, or antibiotic production. We then demonstrate in a spatially explicit, individual-based model that these three mechanisms act similarly by selectively promoting the initial proliferation of preferred strains, that is, by acting as a private resource. The faster early growth of preferred strains, combined with the phenomenon of 'community bistability,' allows those strains to continue to dominate the microbiome even after the private resource is withdrawn or made public. This is because after a beneficial colony reaches a sufficiently large size, it can resist invasion by parasites without further private support from the host. We further explicitly model localized microbial interactions and diffusion dynamics, and we show that an intermediate level of antibiotic diffusion is the most efficient mechanism in promoting preferred strains and that there is a wide range of parameters under which hosts can promote the assembly of a self-sustaining defensive microbiome. This in turn supports the idea that hosts readily evolve to promote host-beneficial defensive microbiomes.


Assuntos
Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/fisiologia , Animais , Antibacterianos/biossíntese , Biologia Computacional , Ecossistema , Modelos Biológicos , Simbiose/fisiologia
13.
Vet Microbiol ; 233: 39-46, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31176410

RESUMO

E5 protein, the major oncoprotein of bovine Deltapapillomavirus (BPV), was found to be expressed in 18 of 21 examined urothelial cancers of cattle. E5 oncoprotein was found to interact with p62 which was degraded through the autophagosome-lysosome pathway as well as LC3-II and appeared to be involved in the phosphorylation of the α-subunit of eukaryotic initiation factor 2 (eIF2α). Autophagy was morphologically documented by transmission electron microscope (TEM) through the detection of double-membrane autophagosomes and autolysosomes. Overexpression of Bag3 known to mediate selective autophagy was also demonstrated. Furthermore, Bag3 and BPV E5 oncoprotein were seen to co-localize with dynein and 14-3-3γ, which suggested that Bag3 could be involved in inducing the retrograde transport of BPV E5 along microtubules to aggresomes, perinuclear sites with high autophagic flux. Electron dense perinuclear structures consistent with aggresomes were also documented by TEM in urothelial cancer cells. Finally, Bag3 was found to also interact with synaptopodin 2 (Synpo2), which would seem to contribute to cargo degradation as it has been shown to facilitate autophagosome formation. This study provides mechanistic insights into the potential role(s) of autophagy in BPV disease, which can help to develop future treatment and control measures for BPV infection. Activation of autophagy correlates positively with BPV infection and may play a role in biological behavior of bladder cancer as urothelial carcinomas of cattle are known to be characterized by a relatively low rate of metastasis.


Assuntos
Autofagia , Papillomavirus Bovino 1/genética , Expressão Gênica , Proteínas Oncogênicas Virais/genética , Neoplasias da Bexiga Urinária/veterinária , Animais , Bovinos , Doenças dos Bovinos/virologia , DNA Viral/genética , DNA Viral/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Redes Reguladoras de Genes , Interações entre Hospedeiro e Microrganismos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Fosforilação , Neoplasias da Bexiga Urinária/virologia , Urotélio/virologia
14.
Nat Med ; 25(7): 1110-1115, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31209335

RESUMO

Neonates are protected from colonizing bacteria by antibodies secreted into maternal milk. Necrotizing enterocolitis (NEC) is a disease of neonatal preterm infants with high morbidity and mortality that is associated with intestinal inflammation driven by the microbiota1-3. The incidence of NEC is substantially lower in infants fed with maternal milk, although the mechanisms that underlie this benefit are not clear4-6. Here we show that maternal immunoglobulin A (IgA) is an important factor for protection against NEC. Analysis of IgA binding to fecal bacteria from preterm infants indicated that maternal milk was the predominant source of IgA in the first month of life and that a relative decrease in IgA-bound bacteria is associated with the development of NEC. Sequencing of IgA-bound and unbound bacteria revealed that before the onset of disease, NEC was associated with increasing domination by Enterobacteriaceae in the IgA-unbound fraction of the microbiota. Furthermore, we confirmed that IgA is critical for preventing NEC in a mouse model, in which pups that are reared by IgA-deficient mothers are susceptible to disease despite exposure to maternal milk. Our findings show that maternal IgA shapes the host-microbiota relationship of preterm neonates and that IgA in maternal milk is a critical and necessary factor for the prevention of NEC.


Assuntos
Enterocolite Necrosante/prevenção & controle , Imunoglobulina A/fisiologia , Adulto , Animais , Enterobacteriaceae/fisiologia , Enterocolite Necrosante/epidemiologia , Feminino , Interações entre Hospedeiro e Microrganismos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez
15.
J Forensic Sci ; 64(6): 1707-1719, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31170333

RESUMO

Multiple methods have been proposed to provide accurate time since death estimations, and recently, the discovery of bacterial community turnover during decomposition has shown itself to have predictable patterns that may prove useful. In this study, we demonstrate the use of metatranscriptomics from the postmortem microbiome to simultaneously obtain community structure and functional data across postmortem intervals (PMIs). We found that bacterial succession patterns reveal similar trends as detected through DNA analysis, such as increasing Clostridiaceae as decomposition occurs, strengthening the reliability of total RNA community analyses. We also provide one of the first analyses of RNA transcripts to characterize bacterial metabolic pathways during decomposition. We found distinct pathways, such as amino acid metabolism, to be strongly up-regulated with increasing PMIs. Elucidating the metabolic activity of postmortem microbial communities provides the first steps to discovering postmortem functional biomarkers since functional redundancy across bacteria may reduce host individual microbiome variability.


Assuntos
Fenômenos Fisiológicos Bacterianos , Mudanças Depois da Morte , RNA Bacteriano/análise , Animais , Medula Óssea/microbiologia , Clostridium perfringens/genética , Clostridium perfringens/fisiologia , Coração/microbiologia , Interações entre Hospedeiro e Microrganismos , Intestinos/microbiologia , Camundongos , Modelos Animais , Reação em Cadeia da Polimerase , RNA Ribossômico 16S , Staphylococcus aureus/genética , Staphylococcus aureus/fisiologia , Estômago/microbiologia
18.
Nat Med ; 25(6): 1001-1011, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31142850

RESUMO

The microbiome of the female reproductive tract has implications for women's reproductive health. We examined the vaginal microbiome in two cohorts of women who experienced normal term births: a cross-sectionally sampled cohort of 613 pregnant and 1,969 non-pregnant women, focusing on 300 pregnant and 300 non-pregnant women of African, Hispanic or European ancestry case-matched for race, gestational age and household income; and a longitudinally sampled cohort of 90 pregnant women of African or non-African ancestry. In these women, the vaginal microbiome shifted during pregnancy toward Lactobacillus-dominated profiles at the expense of taxa often associated with vaginal dysbiosis. The shifts occurred early in pregnancy, followed predictable patterns, were associated with simplification of the metabolic capacity of the microbiome and were significant only in women of African or Hispanic ancestry. Both genomic and environmental factors are likely contributors to these trends, with socioeconomic status as a likely environmental influence.


Assuntos
Microbiota , Gravidez/fisiologia , Vagina/microbiologia , Adulto , Afro-Americanos , Biodiversidade , Estudos de Coortes , Estudos Transversais , Grupo com Ancestrais do Continente Europeu , Feminino , Hispano-Americanos , Interações entre Hospedeiro e Microrganismos/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Microbiota/genética , Microbiota/fisiologia , Classe Social
19.
Int J Med Microbiol ; 309(3-4): 252-257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31079999

RESUMO

Plants are always found together with bacteria and other microbes. Although plants can be attacked by phytopathogenic bacteria, they are more often engaged in neutral or mutualistic bacterial interactions. In the soil, plants associate with rhizobia or other plant growth promoting rhizosphere bacteria; above ground, bacteria colonise plants as epi- and endophytes. For mounting appropriate responses, such as permitting colonisation by beneficial symbionts while at the same time fending off pathogenic invaders, plants need to distinguish between the "good" and the "bad". Plants make use of proteins containing the lysin motif (LysM) for perception of N-acetylglucosamine containing carbohydrate structures, such as chitooligosaccharides functioning as symbiotic nodulation factors or bacterial peptidoglycan. Moreover, plant hydrolytic enzymes of the chitinase family, which are able to cleave bacterial peptidoglycan or chitooligosaccharides, are essential for cellular signalling induced by rhizobial nodulation factors during symbiosis as well as bacterial peptidoglycan during pathogenesis. Hence, LysM receptors seem to work in concert with hydrolytic enzymes that fine-tune ligand availability to either allow symbiotic interactions or trigger plant immunity.


Assuntos
Quitinases/metabolismo , Interações entre Hospedeiro e Microrganismos , Proteínas de Plantas/metabolismo , Plantas/microbiologia , Receptores de Superfície Celular/metabolismo , Bactérias/química , Bactérias/metabolismo , Quitina/análogos & derivados , Quitina/metabolismo , Lisina , Peptidoglicano/metabolismo , Proteínas de Plantas/química , Receptores de Superfície Celular/química , Transdução de Sinais
20.
Microb Pathog ; 132: 325-334, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082529

RESUMO

Specific pathogen-free (SPF) experimental animals are recognized as standard laboratory animals in the fields of biomedical, animal husbandry and veterinary research and production. Intestinal flora plays a critical role in nutrient absorption, improving health and protecting the host from pathogens. We therefore explored the variation and maintenance of intestinal flora in SPF chicks in order to better understand the composition of intestinal microflorain SPF chickens, and provide reference for the study of intestinal flora of SPF experimental animals. Five chicks were randomly selected at each of 14, 28, and 42 days, and ceca were removed for DNA extraction. The Illumina Miseq platform was used for microbiome analysis of the V3-V4 region of the 16S rRNA gene. During the course of chick gut microbiome development, we observed major changes in diversity, especially between day 14 and day 28. Firmicutes, Proteobacteria, and Bacteroidetes were the main bacterial taxa, and Firmicutes increased significantly with age. The genus with the highest relative abundance was Lactobacillus, followed by Faecalibacterium. In addition, while abundance of Ruminococcaceae spp., Ruminococcus, and Blautia increased with age, Lactobacillus, Enterobacteriaceae spp., and Oscillospira decreased with age. Interestingly, the abundance of Faecalibacterium first increased and then decreased over time. The characteristics of SPF chicken gut flora at different ages establish a basis for the regulation of intestinal flora in the early stage of brooding, and also provide a theoretical foundation for controlling and preventing infections and poultry diseases in newborn chickens.


Assuntos
Galinhas/microbiologia , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos/fisiologia , Organismos Livres de Patógenos Específicos , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , DNA Bacteriano/genética , Microbioma Gastrointestinal/genética , Interações entre Hospedeiro e Microrganismos/genética , Intestinos/microbiologia , Doenças das Aves Domésticas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
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