12275 results for ""statistically+reactive"+taxa+in+microbial+community"

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• Gut microbiome profiles according to sex, body mass index and dietary fiber intake

  Findings from recent studies suggest that the community of microbes residing in the human body is important in disease etiology; however, it remains unclear whether personal factors modulate human microbial composition. Studies based on animal models indicate that differences in composition might be attributed to sex-mediated effects. We analyzed the relationship of sex, adiposity, and dietary fiber intake with gut microbial composition using fecal samples from human subjects. We explored the associations of these factors with metrics of community composition and specific taxon abundances. We found that men and women had significantly different microbial community composition and that women had reduced abundance of a major phylum. Adiposity was associated with gut microbiome composition and specifically in women but not in men. Fiber from fruits and vegetables and fiber from beans were each associated with increased abundance of specific bacterial taxa. These findings provide initial indications that sex, adiposity, and dietary fiber might play important roles in influencing the human gut microbiome. Better understanding of these factors may have significant implications for gastrointestinal health and disease prevention.

  Study phs000884

• The Influence of Gut Microbiota on the Speciation and Toxicity of Mercury During Pregnancy

  There are few studies that have characterized maternal gut microbiota and fetal methylmercury exposure, yet microbes likely modulate this relationship. The primary objective of our pilot study was to determine associations between gut microbial taxa and mercury concentrations in multiple biomarkers (stool, hair, and cord blood). Our secondary objective was to determine the contribution of gut microbial mercury methylation to stool methylmercury.

  Study phs000970

• Alterations in the gut microbiome in inflammatory arthritis implicate key taxa and metabolic pathways across arthritis phenotypes

  The gut microbiome has been implicated in several inflammatory conditions, but large-scale metagenomic evaluations have not yet traced the routes by which immunity in the gut affects systemic inflammatory diseases, such as inflammatory arthritis. To characterize the community structure and associated functional processes driving gut microbial involvement in arthritis, we investigated a total of 440 stool shotgun metagenomes comprising 275 adults diagnosed with rheumatoid arthritis, ankylosing spondylitis, or psoriatic arthritis, along with 165 healthy control individuals and individuals with joint pain without an underlying inflammatory cause.

  Study EGAS00001005525

• Enrichment of Lung Microbiome with Supraglottic Taxa which is Associated with Increased Pulmonary Inflammation

  Background: The lung microbiome of healthy individuals frequently harbors oral organisms. Despite evidence that micro-aspiration is commonly associated with smoking-related lung diseases, the effects of lung microbiome enrichment with upper airway taxa on inflammation has not been studied. We hypothesize that the presence of oral microorganisms in the lung microbiome is associated with enhanced pulmonary inflammation. Methods: We sampled bronchoalveolar lavage (BAL) from the lower airways of 29 asymptomatic subjects (9 never-smokers, 14 former-smokers and 6 current-smokers). We quantified, amplified, and sequenced 16S rRNA genes from BAL samples by qPCR and 454 sequencing. Pulmonary inflammation was assessed by exhaled nitric oxide (eNO), BAL lymphocytes and neutrophils. Results: BAL had lower total 16S than supraglottic samples and higher than saline background. Bacterial communities in the lower airway clustered in two distinct groups that we designated as pneumotypes. The rRNA gene concentration and microbial community of the first pneumotype was similar to that of the saline background. The second pneumotype had higher rRNA gene concentration and higher relative abundance of supraglottic-characteristic taxa (SCT), such as Veillonella and Prevotella, and we called it pneumotypeSCT. Smoking had no effect on pneumotype allocation, alpha or beta diversity. PneumotypeSCT was associated with higher BAL lymphocyte-count (p = 0.007), BAL neutrophil-count (p = 0.034) and eNO (p = 0.022). Conclusion: A pneumotype with high relative abundance of supraglottic-characteristic taxa is associated with enhanced subclinical lung inflammation.

  Study phs000633

• Alterations in the gut microbiome implicate key taxa and metabolic pathways across inflammatory arthritis phenotypes

  Musculoskeletal diseases affect up to 20% of adults worldwide. The gut microbiome has been implicated in inflammatory conditions, but large-scale metagenomic evaluations have not yet traced the routes by which immunity in the gut affects inflammatory arthritis. To characterize the community structure and associated functional processes driving gut microbial involvement in arthritis, the Inflammatory Arthritis Microbiome Consortium investigated 440 stool shotgun metagenomes comprising 221 adults diagnosed with rheumatoid arthritis, ankylosing spondylitis, or psoriatic arthritis and 219 healthy controls and individuals with joint pain without an underlying inflammatory cause. Diagnosis explained about 2% of gut taxonomic variability, which is comparable in magnitude to inflammatory bowel disease. We identified several candidate microbes with differential carriage patterns in patients with elevated blood markers for inflammation. Our results confirm and extend previous findings of increased carriage of typically oral and inflammatory taxa and decreased abundance and prevalence of typical gut clades, indicating that distal inflammatory conditions, as well as local conditions, correspond to alterations to the gut microbial composition. We identified several differentially encoded pathways in the gut microbiome of patients with inflammatory arthritis, including changes in vitamin B salvage and biosynthesis and enrichment of iron sequestration. Although several of these changes characteristic of inflammation could have causal roles, we hypothesize that they are mainly positive feedback responses to changes in host physiology and immune homeostasis. By connecting taxonomic alternations to functional alterations, this work expands our understanding of the shifts in the gut ecosystem that occur in response to systemic inflammation during arthritis.

  Dataset EGAD50000000567

• Variation and transmission of the human gut microbiota across generations - shotgun data

  Although composition and functional potential of the human gut microbiota evolve over lifespan, kinship has been identified as a key covariate of microbial community diversification. To date, sharing of microbiota features within families has however mostly been assessed between parents and their direct offspring. Here, we investigate potential transmission and persistence of familial microbiome patterns and microbial genotypes in a family cohort (N=102) spanning three to five generations over the same female bloodline. We observe microbiome community composition to be associated with kinship, with seven (low-abundant) genera displaying familial distribution patterns. While kinship and current cohabitation emerged as closely entangled variables, our explorative analyses of microbial genotype distribution and transmission estimates point at the latter as a key covariate of strain dissemination. Highest potential transmission rates are estimated between sisters and mother-daughter pairs, decreasing with increasing daughter’s age, and being higher among cohabiting pairs than those living apart. Although rare, we do detect potential transmission events spanning three and four generations, primarily involving species of the genera Alistipes and Bacteroides. Overall, while our analyses confirm the existence of family-bound microbiome community profiles, transmission or co-acquisition of bacterial strains appears to be strongly linked to cohabitation.

  Study EGAS00001005649

• Variation and transmission of the human gut microbiota across generations - 16S data

  Although composition and functional potential of the human gut microbiota evolve over lifespan, kinship has been identified as a key covariate of microbial community diversification. To date, sharing of microbiota features within families has however mostly been assessed between parents and their direct offspring. Here, we investigate potential transmission and persistence of familial microbiome patterns and microbial genotypes in a family cohort (N=102) spanning three to five generations over the same female bloodline. We observe microbiome community composition to be associated with kinship, with seven (low-abundant) genera displaying familial distribution patterns. While kinship and current cohabitation emerged as closely entangled variables, our explorative analyses of microbial genotype distribution and transmission estimates point at the latter as a key covariate of strain dissemination. Highest potential transmission rates are estimated between sisters and mother-daughter pairs, decreasing with increasing daughter’s age, and being higher among cohabiting pairs than those living apart. Although rare, we do detect potential transmission events spanning three and four generations, primarily involving species of the genera Alistipes and Bacteroides. Overall, while our analyses confirm the existence of family-bound microbiome community profiles, transmission or co-acquisition of bacterial strains appears to be strongly linked to cohabitation.

  Study EGAS00001005651

• Characterizing microbiome-directed fibre snacks in gnotobiotic mice and humans

  Knowledge of the interrelationships between what we eat and the configurations of our gut microbial communities is providing important insights into how food components that are not directly metabolized by human enzymes are linked to our physiology and health status. Changing food preferences brought about by Westernization that have deleterious health effects1,2, plus rapid population expansion, ongoing challenges to sustainable agriculture, and other forces contributing to increased food insecurity, are catalyzing efforts to identify more nutritious and affordable foods3. The gut microbial community is complex, dynamic, and exhibits considerable intra- and interpersonal variation in its composition and functions. The massive number of potential interactions between its components makes it challenging to define the mechanisms by which food ingredients affect community properties. There is also a paucity of information about the ‘bioactive’ ingredients of foods that influence the fitness and expressed functions of community members. Here, plant fibres, from different sustainable sources and targeting distinct features of obese human gut microbiomes in gnotobiotic mice, were formulated into snack prototypes and used to supplement controlled diets consumed by overweight and obese adults; the results revealed fibre-specific changes in their microbiomes that were linked to changes in their plasma proteomes indicative of altered physiologic state.

  Study EGAS00001005268

• Upper respiratory microbiome of COVID-19 patients

  Understanding the pathology of COVID-19 is a global research priority. Early evidence suggests that the microbiome may be playing a role in disease progression, yet current studies report contradictory results. Here, we examine potential confounders in COVID-19 microbiome studies by analyzing the upper respiratory tract microbiome in well-phenotyped COVID-19 patients and controls combining microbiome sequencing, viral load determination, and immunoprofiling. We found that time in the intensive care unit and the type of oxygen support explained the most variation within the upper respiratory tract microbiome, dwarfing (non-significant) effects from viral load, disease severity, and immune status. Specifically, mechanical ventilation was linked to altered community structure, lower species- and higher strain-level diversity, and significant shifts in oral taxa previously associated with COVID-19.

  Study EGAS00001004951

• Quantitative microbiome profiling disentangles inflammation- and bile duct obstruction-associated microbiota alterations across IBD/PSC diagnoses

  Disease-association microbiome dataset comprising 106 primary sclerosing cholangitis and/or inflammatory bowel disease (PSC/IBD) patients. Assessing quantitative taxon abundances, we study microbiome alterations beyond symptomatic stool moisture variation. We observe a high prevalence of a low cell count Bacteroides2 enterotype across patient groups when compared to healthy controls, with microbial loads correlating inversely with intestinal and systemic inflammation markers. Quantitative analyses allow us to differentiate between taxa associated to either intestinal inflammation severity (Fusobacterium) or cholangitis/biliary obstruction (Enterococcus) among previously suggested PSC marker genera. We identify and validate a near-exclusion pattern between the inflammation-associated Fusobacterium and Veillonella genera, with Fusobacterium detection being restricted to Crohn’s disease (CD) and PSC-CD patients. Overall, through absolute quantification and confounder control, we single out clear-cut microbiome markers associated to pathophysiological manifestations and disease diagnosis.

  Study EGAS00001003600

• Insights into Adult Gut Microbiota Composition Using the Estonian Cohort

  This study explores the gut microbiota of 1,826 adult individuals, predominantly from the Estonian population. The cohort includes 16S rRNA gene V4 region amplicon sequencing data along with metadata, such as age, sex, health status, anthropometric parameters, and stool consistency. The research aims to characterise the microbial community structure, identify distinct enterotypes, and examine their associations with host characteristics. The dataset provides a valuable reference for understanding gut microbiota composition and supports research in personalised nutrition and lifestyle-related health strategies.

  Study EGAS50000001611

• Characterization of the Gut-Associated Microbiome in Inflammatory Pouch Complications Following Ileal Pouch-Anal Anastomosis

  This study involved evaluation of the tissue associated microbiome of the ileal pouch following surgery for ulcerative colitis (UC) or familial adenomatous polyposis (FAP). Individuals were recruited, with biopsies taken from the ileal pouch and the pre-pouch ileum, microbial DNA was extracted and sequenced using 454 pyrosequencing. Total bacterial community structure and abundance were evaluated to determine which changes were characteristic of inflammatory phenotypes including pouchitis (inflammation of the ileal pouch) and a Crohn's disease-like phenotype.

  Study phs000659

• Metagenomic Analysis of the Structure and Function of the Human Gut Microbiota in Crohn's Disease

  Inflammatory bowel diseases (IBD), such as Crohn's disease, are chronic, immunologically mediated disorders that have severe medical consequences. The current hypothesis is that these diseases are due to an overly aggressive immune response to a subset of commensal enteric bacteria. Studies to date on IBD have suggested that the disorder may be caused by a combination of bacteria and host susceptibility; however the etiologies of these diseases remain an enigma. In this application, we propose to develop and demonstrate the ability to profile Crohn's disease at an unprecedented molecular level by elucidation of specific biomarkers (bacterial strains, genes, or proteins) that correlate to disease symptoms. To achieve this goal, we will employ a multidisciplinary approach based on metagenomic and metaproteomic molecular tools to elucidate the composition of the commensal microbiota in monozygotic twins that are either healthy or exhibit Crohn's disease (for concordant, both are diseased; for discordant, one is healthy and one is diseased). The central hypotheses of this proposal are (1) that specific members and/or functional activities of the gastrointestinal (GI) microbiota differ in patients with Crohn's disease as compared to healthy individuals, and (2) that it will be possible to elucidate microbial signatures which correlate with the occurrence and progression of this disease by integration of data obtained from 16S rRNA-based molecular fingerprinting, metagenomics, and metaproteomics approaches. To address these hypotheses, three specific aims are proposed: 1) Obtain data on community gene content (metagenome) in a subset of healthy twins and twins with Crohn's Disease to assess potential differences in the metabolic capabilities of the gut microbiota associated with CD, 2) Obtain data on community protein content (metaproteome) in a subset of healthy twins and twins with Crohn's Disease to assess the state of expressed proteins associated with CD, 3) Apply various statistical clustering and classification methods to correlate/associate microbial community composition, gene and protein content with patient metadata, including metabolite profiles and clinical phenotype. The ultimate goal of these efforts is to identify novel biomarkers for non-invasive diagnostics of CD and to eventually identify drug targets (i.e. bacterial strains) for cure or suppression of disease symptoms. PUBLIC HEALTH RELEVANCE: This study aims to unravel the contribution of the bacteria that normally inhabit the human gastrointestinal tract to Crohn's disease by using a multidisciplinary approach to study changes in the structure and function of gut microbial communities in three sets of patient cohorts who have Crohn's disease. These results will be compared with those obtained from the study of healthy individuals and have the potential to identify new biomarkers of disease severity, location, and progression.

  Study phs000257

• Profiling of human fecal microbiota for succinate consumption

  The objective of this study was to identify the bacterial taxa responsible for succinate consumption in human gut microbiomes. We enriched fresh stool from healthy donors in growth medium with and without supplemented succinate. We then measured metabolite concentrations and bacterial composition in the stool and enrichment samples.

  Study EGAS50000000519

• The Microbial Ecology of Bacterial Vaginosis: A Fine Scale Resolution Metagenomic Analysis

  Archived self-collected vaginal swabs were utilized from a pilot study of vaginal douching cessation (NIH/NIAID R03-AI061131). Thirty-nine non-pregnant, reproductive-age women who reported the use of vaginal douche products in the two months prior to screening were enrolled. Thirty-three of these successfully completed the 16-week longitudinal study. Participants self-collected vaginal swabs and smears twice weekly. We report sequences based on the analysis of 16S rRNA gene sequences amplified from whole genomic DNA isolated from the swabs. Bacterial vaginosis (BV) is defined by Gram's stain of vaginal fluid (Nugent's score =7). The large body of information generated will facilitate understanding of vaginal microbial community dynamics, the etiology of BV, and drive the development of better diagnostic tools for BV. Furthermore, it is hoped that the information will enable a more personalized treatment of BV and ultimately, prevent adverse sequelae associated with BV.

  Study phs000261

• Whole-Genome Shotgun Metagenomic Analysis of Rectal Mucus for Colorectal Cancer Detection

  This study evaluates the use of rectal mucus as a minimally invasive biospecimen for colorectal cancer (CRC) detection through whole-genome shotgun metagenomic sequencing. 408 rectal mucus samples were collected from patients suspected to have colorectal cancer and sequenced. These samples were analyzed to characterize microbial community composition and its association with CRC stage and anatomical site. These data provide insights into tumor-proximal microbiome signatures and demonstrate the potential of rectal mucus sampling for early and accurate CRC diagnosis. This is 1 of 4 sequencing experiments on the same sample type.

  Study EGAS50000001310

• Whole-genome shotgun metagenomic sequencing of rectal mucus from patients suspected to have colorectal cancer

  This dataset contains whole-genome shotgun metagenomic sequencing data of 408 rectal mucus samples from patients suspected to have colorectal cancer and healthy controls. Sequencing was performed on the Illumina NovaSeq platform, producing paired-end FASTQ files. These data support microbial community profiling and biomarker discovery analyse

  Dataset EGAD50000001867

• IAMC adult cross sectional

  Data access committee for the manuscript "Alterations in the gut microbiome in inflammatory arthritis implicate key taxa and metabolic pathways across arthritis phenotypes"

  Dac EGAC50000000272

• The Placenta Harbors a Unique Microbiome

  This study is to investigate placental microbiome through 16S rDNA-based and whole genome shotgun metagenomic sequencing. Identified taxa and their gene carriage patterns were compared to other human body sites niches. The placental microbiome profiles were most akin to the human oral microbiome.

  Study phs000735

• Microbial signatures and innate immune gene expression in lamina propria phagocytes of inflammatory bowel diseases patients

  The microbial populations associated with the lamina propria phagocyte population in CD and UC patients was examined. Specifically, the differences between phagocyte-associated microbiota (PAM) and mucosa-associated microbiota were determined.

  Study EGAS00001003105

• Microbial infections in Multiple Sclerosis Samples

  In this study, we have examined microbial infection in brain tissue from 9 control samples from healthy patients and 10 samples from patients diagnosed with Multiple sclerosis, by Next-generation sequencing NGS using Miseq sequencing platform (Illumina).

  Dataset EGAD00001004085

• The Thrifty Microbiome: The Role of the Gut Microbiota in Obesity in the Amish

  Emerging evidence that the gut microbiota may contribute in important ways to human health and disease has led us and others to hypothesize that both symbiotic and pathological relationships between gut microbes and their host may be key contributors to obesity and the metabolic complications of obesity. Our "Thrifty Microbiome Hypothesis" poses that gut microbiota play a key role in human energy homeostasis. Specifically, constituents of the gut microbial community may introduce a survival advantage to its host in times of nutrient scarcity, promoting positive energy balance by increasing efficiency of nutrient absorption and improving metabolic efficiency and energy storage. However, in the presence of excess nutrients, fat accretion and obesity may result, and in genetically predisposed individuals, increased fat mass may result in preferential abdominal obesity, ectopic fat deposition (liver, muscle), and metabolic complications of obesity (insulin resistance, hypertension, hyperlipidemia). Furthermore, in the presence of excess nutrients, a pathological transition of the gut microbial community may occur, causing leakage of bacterial products into the intestinal lymphatics and portal circulation, thereby inducing an inflammatory state, further aggravating metabolic syndrome traits and accelerating atherosclerosis. This pathological transition and the extent to which antimicrobial leakage occurs and causes inflammatory and other maladaptive sequelae of obesity may also be influenced by host factors, including genetics. In the proposed study, we will directly test the Thrifty Microbiome Hypothesis by performing detailed genomic and functional assessment of gut microbial communities in intensively phenotyped and genotyped human subjects before and after intentional manipulation of the gut microbiome. To address these hypotheses, five specific aims are proposed: (1) enroll three age- and sex-matched groups from the Old Order Amish: (i) 50 obese subjects (BMI > 30 kg/m2) with metabolic syndrome, (ii) 50 obese subjects (BMI > 30 kg/m2) without metabolic syndrome, and (iii) 50 non-obese subjects (BMI < 25 kg/m2) without metabolic syndrome and characterize the architecture of the gut microbiota from the subjects enrolled in this study by high-throughput sequencing of 16S rRNA genes; (2) characterize the gene content (metagenome) to assess the metabolic potential of the gut microbiota in 75 subjects to determine whether particular genes or pathways are correlated with disease phenotype; (3) characterize the transcriptome in 75 subjects to determine whether differences in gene expression in the gut microbiota are correlated with disease phenotype, (4) determine the effect of manipulation of the gut microbiota with antibiotics on energy homeostasis, inflammation markers, and metabolic syndrome traits in 50 obese subjects with metabolic syndrome and (5) study the relationship between gut microbiota and metabolic and cardiovascular disease traits, weight change, and host genomics in 1,000 Amish already characterized for these traits and in whom 500K Affymetrix SNP chips have already been completed. These studies will provide our deepest understanding to date of the role of gut microbes in terms of 'who's there?', 'what are they doing?', and 'how are they influencing host energy homeostasis, obesity and its metabolic complications? PUBLIC HEALTH RELEVANCE: This study aims to unravel the contribution of the bacteria that normally inhabit the human gastrointestinal tract to the development of obesity, and its more severe metabolic consequences including cardiovascular disease, insulin resistance and Type II diabetes. We will take a multidisciplinary approach to study changes in the structure and function of gut microbial communities in three sets of Old Order Amish patients from Lancaster, Pennsylvania: obese patients, obese patients with metabolic syndrome and non-obese individuals. The Old Order Amish are a genetically closed homogeneous Caucasian population of Central European ancestry ideal for genetic studies. These works have the potential to provide new mechanistic insights into the role of gut microflora in obesity and metabolic syndrome, a disease that is responsible for significant morbidity in the adult population, and may ultimately lead to novel approaches for prevention and treatment of this disorder.

  Study phs000258

• Study of the Human Skin Metagenome Associated with Acne

  Studies have emphasized the importance of disease-associated microorganisms in perturbed communities, however, the protective roles of commensals are largely under recognized and poorly understood. Using acne as a model disease, we investigated the determinants of the overall virulence property of the skin microbiota when disease- and health-associated organisms coexist in the community. By ultra-deep metagenomic shotgun sequencing, we revealed higher relative abundances of propionibacteria and Propionibacterium acnes phage in healthy skin. In acne patients, the microbiome composition at the species level and at P. acnes strain level was more diverse than in healthy individuals, with enriched virulence-associated factors and reduced abundance of metabolic synthesis genes. Based on the abundance profiles of the metagenomic elements, we constructed a quantitative prediction model, which classified the clinical states of the host skin with high accuracy in both our study cohort (85%) and an independent sample set (86%). Our results suggest that the balance between metagenomic elements, not the mere presence of disease-associated strains, shapes the overall virulence property of the skin microbiota. This study provides new insights into the microbial mechanism of acne pathogenesis and suggests probiotic and phage therapies as potential acne treatments to modulate the skin microbiota and to maintain skin health.

  Study phs001655

• The Vaginal Microbiome: Disease, Genetics and the Environment

  The vagina is an interactive interface with the environment, and as such is covered by a protective epithelial surface. This surface is colonized by a biofilm consisting of bacteria and other microorganisms, which through a variety of mechanisms serve to protect the host from invasion by pathogens. Alterations in the normal vaginal microflora; i.e., dysbioses, particularly those associated with bacterial vaginosis, the most common disorder of the female reproductive tract, contribute to risk of sexually transmitted infections, infection by HIV, and are associated with increased risk of adverse pregnancy outcomes including but not limited to spontaneous preterm birth. Physiologic alterations in the host (e.g., menopause and pregnancy), which are beginning to be investigated as potential selective conditions for change in the "normal" vaginal flora, and their impact on disease susceptibility and transmission, remain to be more definitively elucidated. The effects of chronically abnormal physiologic states (e.g., diabetes mellitus) on normal vaginal flora have not been well described or studied. Finally, an almost unexplored area of inquiry is the genetic contribution, including race/ethnicity, to the establishment and maintenance of a "normal" vaginal flora, under normal and physiologically altered circumstances. Our research will shed light on how the vaginal microbiome contributes to adverse obstetrical outcomes and sexually transmitted infections in diverse populations. This project addresses the following questions: First: Do the genes of the host contribute to the composition of the vaginal microbiome? We hypothesize that a woman's genetic composition significantly affects the ability of certain commensal, parasitic and pathogenic microbes to colonize and/or infect the genital tract. Thus, we will compare and quantify the microbial populations inhabiting the vaginas of monozygotic and dizygotic twins from the Mid Atlantic Twin Registry, and, in the process, address the question of whether there is a relationship between the microbiomes of the vagina, mouth and GI tract. Second: What changes in the vaginal microbiome are associated with common physiological perturbations or non-infectious pathological states of the host?We hypothesize that "altered" physiologic (pregnancy, menopause) and pathologic (chronic disease, hysterectomy) conditions, or environmental "exposures" (exogenous hormones, antibiotics, chronic immunosuppressant, smoking; douching) can predictably alter the vaginal microenvironment. These alterations will lead to changes in microbial populations within the vagina. Changes in the microbial populations may have impacts, positive or more likely negative, on the spontaneous and future well-being of the affected individual. We are characterizing the effects of these "altered" physiologic and pathologic conditions, and environmental exposures, on the composition of the vaginal microbiome. Finally, we are examining the impact of the important physiological changes incurred during pregnancy on the composition of the microbiome of the female reproductive tract. Third: What changes in the vaginal microbiome are associated with relevant infectious diseases and conditions? We are testing the hypothesis that infectious diseases predictably alter the vaginal microbiome, and that these changes have an impact on the disease susceptibility, process, and outcome. A predilection for bacterial vaginosis, vaginitis, HIV infection, or other sexually transmitted diseases, is likely associated with a women's vaginal microbial composition. Thus, we will characterize samples from women with a variety of these infectious conditions to determine the contribution of their microbiomes to the disease process and susceptibility. We are addressing these questions using a combination of high throughput 'nextgen' sequencing technologies. Early studies were performed using the Roche 454 FLX and the first generation Illumina Genome Analyzer II instruments and more recently employing Illumina MiSeq and HiSeq 2500 and 4000 platforms, installed in the Genomics Core of the Nucleic Acids Research Facilities at VCU. Thus, segments of the 16S rRNA genes are amplified from the complex samples taken from various target sites in and around the vagina of each study participant. These segments are sequenced and subjected to taxonomic classification protocols to identify and quantify the bacterial taxa present in each sample. Additionally, total DNA isolated from these samples are subjected to shotgun sequence analysis to empirically reconstruct the metabolic potential of these microbiomes. Finally, specific bacterial clones are completely sequenced and analyzed to associate the unavoidable strain and isolate diversity with the clinical phenotypes presented.

  Study phs000256

• Microbiome-Host Interactions in Oral Squamous Cell Carcinoma: a Metatranscriptomic Exploratory Study

  Oral cancer (predominantly squamous cell carcinoma; OSCC) is the 14th most prevalent malignancy worldwide, accounting for more than 300,000 new cases and 145,000 deaths annually. Despite advances in cancer treatment modalities, OSCC continues to have poor prognosis with 5-year survival rates less than 50%. Although use of tobacco and alcohol consumption constitute the major risk factors, there is emerging evidence for the role of the microbiome in OSCC. However, studies on the association between the microbiome and OSCC has so far focused on compositional analysis and has been largely limited to the bacterial component of the microbiome. The aim of this study is to characterize the transcriptional activity (function) as well as composition of the multi-kingdom microbiome associated with OSCC and correlate it with the gene expression of the host using ultra-deep metatranscriptome sequencing, which will provide new insight into the role of the microbiome in OSCC and the possible mechanisms by which the tumor’s microbial community may influence on its behavior. This project comprises RNA-Seq data from twenty OSCC tumor/normal tissue pairs and twenty tongue scraping samples from healthy controls. However, due to consent constraints, the human sequences from the control data are filtered out.

  Study phs002678