scholarly journals Evaluative Profiling of Arsenic Sensing and Regulatory Systems in the Human Microbiome Project Genomes

2014 ◽  
Vol 7 ◽  
pp. MBI.S18076 ◽  
Author(s):  
Raphael D. Isokpehi ◽  
Udensi K. Udensi ◽  
Shaneka S. Simmons ◽  
Antoinesha L. Hollman ◽  
Antia E. Cain ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Visual Analytics ◽  
Energy Production ◽  
Human Microbiome ◽  
Human Microbiome Project ◽  
Environmental Chemicals ◽  
Arsenic Content ◽  
Protein Families ◽  
Arsenic Resistance ◽  
Cellular Energy

The influence of environmental chemicals including arsenic, a type 1 carcinogen, on the composition and function of the human-associated microbiota is of significance in human health and disease. We have developed a suite of bioinformatics and visual analytics methods to evaluate the availability (presence or absence) and abundance of functional annotations in a microbial genome for seven Pfam protein families: As(III)-responsive transcriptional repressor (ArsR), anion-transporting ATPase (ArsA), arsenical pump membrane protein (ArsB), arsenate reductase (ArsC), arsenical resistance operon transacting repressor (ArsD), water/glycerol transport protein (aquaporins), and universal stress protein (USP). These genes encode function for sensing and/or regulating arsenic content in the bacterial cell. The evaluative profiling strategy was applied to 3,274 genomes from which 62 genomes from 18 genera were identified to contain genes for the seven protein families. Our list included 12 genomes in the Human Microbiome Project (HMP) from the following genera: Citrobacter, Escherichia, Lactobacillus, Providencia, Rhodococcus, and Staphylococcus. Gene neighborhood analysis of the arsenic resistance operon in the genome of Bacteroides thetaiotaomicron VPI-5482, a human gut symbiont, revealed the adjacent arrangement of genes for arsenite binding/transfer (ArsD) and cytochrome c biosynthesis (DsbD_2). Visual analytics facilitated evaluation of protein annotations in 367 genomes in the phylum Bacteroidetes identified multiple genomes in which genes for ArsD and DsbD_2 were adjacently arranged. Cytochrome c, produced by a posttranslational process, consists of heme-containing proteins important for cellular energy production and signaling. Further research is desired to elucidate arsenic resistance and arsenic-mediated cellular energy production in the Bacteroidetes.

scholarly journals A most wanted list of conserved protein families with no known domains

2017 ◽  
Author(s):  
Stacia K. Wyman ◽  
Aram Avila-Herrera ◽  
Stephen Nayfach ◽  
Katherine S. Pollard
Keyword(s):  
Functional Annotation ◽  
Functional Characterization ◽  
Human Microbiome ◽  
Human Microbiome Project ◽  
Protein Domain ◽  
Protein Families ◽  
Bioinformatics Pipeline ◽  
Metagenomics Data ◽  
Sequence Databases

AbstractThe number and proportion of genes with no known function are growing rapidly. To quantify this phenomenon and provide criteria for prioritizing genes for functional characterization, we developed a bioinformatics pipeline that identifies robustly defined protein families with no annotated domains, ranks these with respect to phylogenetic breadth, and identifies them in metagenomics data. We applied this approach to 271 965 protein families from the SFams database and discovered many with no functional annotation, including >118 000 families lacking any known protein domain. From these, we prioritized 6 668 conserved protein families with at least three sequences from organisms in at least two distinct classes. These Function Unknown Families (FUnkFams) are present in Tara Oceans Expedition and Human Microbiome Project metagenomes, with distributions associated with sampling environment. Our findings highlight the extent of functional novelty in sequence databases and establish an approach for creating a “most wanted” list of genes to characterize.

scholarly journals The Role of the Human Microbiome in Chemical Toxicity

2019 ◽  
Vol 38 (4) ◽  
pp. 251-264 ◽  
Author(s):  
Jason M. Koontz ◽  
Blair C. R. Dancy ◽  
Cassandra L. Horton ◽  
Jonathan D. Stallings ◽  
Valerie T. DiVito ◽  
...  
Keyword(s):  
Health Outcomes ◽  
Human Microbiome ◽  
Chemical Exposure ◽  
Environmental Chemicals ◽  
Microbial Interactions ◽  
World Population ◽  
Toxic Exposure ◽  
Chemical Toxicity ◽  
Microbial Enzymes ◽  
Overwhelming Evidence

There is overwhelming evidence that the microbiome must be considered when evaluating the toxicity of chemicals. Disruption of the normal microbial flora is a known effect of toxic exposure, and these disruptions may lead to human health effects. In addition, the biotransformation of numerous compounds has been shown to be dependent on microbial enzymes, with the potential for different host health outcomes resulting from variations in the microbiome. Evidence suggests that such metabolism of environmental chemicals by enzymes from the host's microbiota can affect the toxicity of that chemical to the host. Chemical-microbial interactions can be categorized into two classes: Microbiome Modulation of Toxicity (MMT) and Toxicant Modulation of the Microbiome (TMM). MMT refers to transformation of a chemical by microbial enzymes or metabolites to modify the chemical in a way that makes it more or less toxic. TMM is a change in the microbiota that results from a chemical exposure. These changes span a large magnitude of effects and may vary from microbial gene regulation, to inhibition of a specific enzyme, to the death of the microbes. Certain microbiomes or microbiota may become associated with different health outcomes, such as resistance or susceptibility to exposure to certain toxic chemicals, the ability to recover following a chemical-induced injury, the presence of disease-associated phenotypes, and the effectiveness of immune responses. Future work in toxicology will require an understanding of how the microbiome interacts with toxicants to fully elucidate how a compound will affect a diverse, real-world population.

scholarly journals Sequence Comparison of Vaginolysin from Different Gardnerella Species

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 86
Author(s):  
Erin M. Garcia ◽  
Myrna G. Serrano ◽  
Laahirie Edupuganti ◽  
David J. Edwards ◽  
Gregory A. Buck ◽  
...  
Keyword(s):  
Amino Acid ◽  
Human Microbiome ◽  
Human Microbiome Project ◽  
Distinct Species ◽  
Vaginal Swab ◽  
Metagenomic Data ◽  
Gardnerella Vaginalis ◽  
Vaginal Epithelial Cells ◽  
Species Specific

Gardnerella vaginalis has recently been split into 13 distinct species. In this study, we tested the hypotheses that species-specific variations in the vaginolysin (VLY) amino acid sequence could influence the interaction between the toxin and vaginal epithelial cells and that VLY variation may be one factor that distinguishes less virulent or commensal strains from more virulent strains. This was assessed by bioinformatic analyses of publicly available Gardnerella spp. sequences and quantification of cytotoxicity and cytokine production from purified, recombinantly produced versions of VLY. After identifying conserved differences that could distinguish distinct VLY types, we analyzed metagenomic data from a cohort of female subjects from the Vaginal Human Microbiome Project to investigate whether these different VLY types exhibited any significant associations with symptoms or Gardnerella spp.-relative abundance in vaginal swab samples. While Type 1 VLY was most prevalent among the subjects and may be associated with increased reports of symptoms, subjects with Type 2 VLY dominant profiles exhibited increased relative Gardnerella spp. abundance. Our findings suggest that amino acid differences alter the interaction of VLY with vaginal keratinocytes, which may potentiate differences in bacterial vaginosis (BV) immunopathology in vivo.

scholarly journals A vércukorértékek nem feltétlenül jellemzik megfelelően a sejtanyagcsere-állapotot

2017 ◽  
Vol 158 (11) ◽  
pp. 409-417
Author(s):  
Kornél Simon ◽  
István Wittmann
Keyword(s):  
Diabetes Mellitus ◽  
Blood Glucose ◽  
Blood Glucose Level ◽  
Glucose Level ◽  
Energy Production ◽  
Cellular Metabolism ◽  
Transport Parameter ◽  
Metabolic State ◽  
Cellular Energy ◽  
Acute And Chronic Stress

Abstract: In clinical recommendations the normalized blood glucose level is declared as the main target in therapy of diabetes mellitus, i.e. the achievement of euglycemia is the main therapeutic goal. This approach suggests, that the normal blood glucose value is the marker of the normal carbohydrate metabolism (eumetabolism), and vice versa: hyperglycemia is associated with abnormal metabolism (dysmetabolism). However the question arises, whether identical blood glucose values do reflect the same intracellular biochemical mechanisms? On the basis of data published in the literature authors try to answer these questions by studying the relations between the short/longterm blood glucose level and the cellular metabolism in different clinical settings characterized by divergent pathophysiological parameters. The correlations between blood glucose level and cellular metabolism in development of micro-, and macroangiopathy, in the breakthrough phenomenon, as well as during administration of metabolic promoters, the discrepancies of relation between blood glucose values and cellular metabolism in type 1, and type 2 diabetes mellitus, furthermore association between blood glucose value and myocardial metabolism in acute and chronic stress were analyzed. Authors conclude, that the actual blood glucose values reveal the actual cellular metabolism in a very variable manner: neither euglycemia does mandatorily indicate eumetabolism (balance of cellular energy production), nor hyperglycemia is necessarily a marker of abnormal metabolic state (dept of cellular energy production). Moreover, at the same actual blood glucose level both the metabolic efficacy of the same organ may sharply vary, and the intracellular biochemical machinery could also be very different. In case of the very same longterm blood glucose level the metabolic state of the different organs could be very variable: some organs show an energetically balanced metabolism, while others produce a significant deficit. These inconsistencies between blood glucose level and cellular metabolism can be explained by the fact, that blood glucose value is a transport parameter, reflecting the actual steady state of glucose transport from the carbohydrate pools into the blood, and that from the blood into the tissues. Without knowing the speed of these transports of opposite direction, the blood glucose value per se can not reveal the quantitative and qualitative characteristics of cellular metabolism. Orv. Hetil., 2017, 158(11), 409–417.

scholarly journals Competition among Nasal Bacteria Suggests a Role for Siderophore-Mediated Interactions in Shaping the Human Nasal Microbiota

2018 ◽  
Vol 85 (10) ◽  
Author(s):  
Reed M. Stubbendieck ◽  
Daniel S. May ◽  
Marc G. Chevrette ◽  
Mia I. Temkin ◽  
Evelyn Wendt-Pienkowski ◽  
...  
Keyword(s):  
Nasal Cavity ◽  
Iron Acquisition ◽  
Interference Competition ◽  
Human Microbiome ◽  
Human Microbiome Project ◽  
Siderophore Production ◽  
Coagulase Negative Staphylococci ◽  
Exploitation Competition ◽  
Content Type

ABSTRACTResources available in the human nasal cavity are limited. Therefore, to successfully colonize the nasal cavity, bacteria must compete for scarce nutrients. Competition may occur directly through interference (e.g., antibiotics) or indirectly by nutrient sequestration. To investigate the nature of nasal bacterial competition, we performed coculture inhibition assays between nasalActinobacteriaandStaphylococcusspp. We found that isolates of coagulase-negative staphylococci (CoNS) were sensitive to growth inhibition byActinobacteriabut thatStaphylococcus aureusisolates were resistant to inhibition. AmongActinobacteria, we observed thatCorynebacteriumspp. were variable in their ability to inhibit CoNS. We sequenced the genomes of 10Corynebacteriumspecies isolates, including 3Corynebacterium propinquumisolates that strongly inhibited CoNS and 7 otherCorynebacteriumspecies isolates that only weakly inhibited CoNS. Using a comparative genomics approach, we found that theC. propinquumgenomes were enriched in genes for iron acquisition and harbored a biosynthetic gene cluster (BGC) for siderophore production, absent in the noninhibitoryCorynebacteriumspecies genomes. Using a chrome azurol S assay, we confirmed thatC. propinquumproduced siderophores. We demonstrated that iron supplementation rescued CoNS from inhibition byC. propinquum, suggesting that inhibition was due to iron restriction through siderophore production. Through comparative metabolomics and molecular networking, we identified the siderophore produced byC. propinquumas dehydroxynocardamine. Finally, we confirmed that the dehydroxynocardamine BGC is expressedin vivoby analyzing human nasal metatranscriptomes from the NIH Human Microbiome Project. Together, our results suggest that bacteria produce siderophores to compete for limited available iron in the nasal cavity and improve their fitness.IMPORTANCEWithin the nasal cavity, interference competition through antimicrobial production is prevalent. For instance, nasalStaphylococcusspecies strains can inhibit the growth of other bacteria through the production of nonribosomal peptides and ribosomally synthesized and posttranslationally modified peptides. In contrast, bacteria engaging in exploitation competition modify the external environment to prevent competitors from growing, usually by hindering access to or depleting essential nutrients. As the nasal cavity is a nutrient-limited environment, we hypothesized that exploitation competition occurs in this system. We determined thatCorynebacterium propinquumproduces an iron-chelating siderophore, and this iron-sequestering molecule correlates with the ability to inhibit the growth of coagulase-negative staphylococci. Furthermore, we found that the genes required for siderophore production are expressedin vivo. Thus, although siderophore production by bacteria is often considered a virulence trait, our work indicates that bacteria may produce siderophores to compete for limited iron in the human nasal cavity.

scholarly journals MetaCompass: Reference-guided Assembly of Metagenomes

2017 ◽  
Author(s):  
Victoria Cepeda ◽  
Bo Liu ◽  
Mathieu Almeida ◽  
Christopher M. Hill ◽  
Sergey Koren ◽  
...  
Keyword(s):  
De Novo ◽  
Human Microbiome ◽  
Human Microbiome Project ◽  
Bacterial Genomes ◽  
Guided Assembly ◽  
Metagenomic Assembly

ABSTRACTMetagenomic studies have primarily relied on de novo approaches for reconstructing genes and genomes from microbial mixtures. While database driven approaches have been employed in certain analyses, they have not been used in the assembly of metagenomes. Here we describe the first effective approach for reference-guided metagenomic assembly of low-abundance bacterial genomes that can complement and improve upon de novo metagenomic assembly methods. When combined with de novo assembly approaches, we show that MetaCompass can generate more complete assemblies than can be obtained by de novo assembly alone, and improve on assemblies from the Human Microbiome Project (over 2,000 samples).

scholarly journals Misclassification of a whole genome sequence reference defined by the Human Microbiome Project: a detrimental carryover effect to microbiome studies

2019 ◽  
Author(s):  
DJ Darwin R. Bandoy ◽  
B Carol Huang ◽  
Bart C. Weimer
Keyword(s):  
Human Microbiome ◽  
Human Microbiome Project ◽  
Outbreak Detection ◽  
Whole Genome Sequence ◽  
Reference Database ◽  
Whole Genome ◽  
Reference Species ◽  
Genome Sequences ◽  
Genome Homology ◽  
Microbiome Data

AbstractTaxonomic classification is an essential step in the analysis of microbiome data that depends on a reference database of whole genome sequences. Taxonomic classifiers are built on established reference species, such as the Human Microbiome Project database, that is growing rapidly. While constructing a population wide pangenome of the bacterium Hungatella, we discovered that the Human Microbiome Project reference species Hungatella hathewayi (WAL 18680) was significantly different to other members of this genus. Specifically, the reference lacked the core genome as compared to the other members. Further analysis, using average nucleotide identity (ANI) and 16s rRNA comparisons, indicated that WAL18680 was misclassified as Hungatella. The error in classification is being amplified in the taxonomic classifiers and will have a compounding effect as microbiome analyses are done, resulting in inaccurate assignment of community members and will lead to fallacious conclusions and possibly treatment. As automated genome homology assessment expands for microbiome analysis, outbreak detection, and public health reliance on whole genomes increases this issue will likely occur at an increasing rate. These observations highlight the need for developing reference free methods for epidemiological investigation using whole genome sequences and the criticality of accurate reference databases.

scholarly journals Mouse Gut Microbiome-Encoded β-Glucuronidases Identified Using Metagenome Analysis Guided by Protein Structure

mSystems ◽  
2019 ◽  
Vol 4 (4) ◽  
Author(s):  
Benjamin C. Creekmore ◽  
Josh H. Gray ◽  
William G. Walton ◽  
Kristen A. Biernat ◽  
Michael S. Little ◽  
...  
Keyword(s):  
Protein Structure ◽  
Active Site ◽  
Human Microbiome ◽  
Drug Efficacy ◽  
Human Microbiome Project ◽  
Structural Features ◽  
Model Organisms ◽  
Mouse Strains ◽  
Sequencing Data ◽  
Metagenome Analysis

ABSTRACT Gut microbial β-glucuronidase (GUS) enzymes play important roles in drug efficacy and toxicity, intestinal carcinogenesis, and mammalian-microbial symbiosis. Recently, the first catalog of human gut GUS proteins was provided for the Human Microbiome Project stool sample database and revealed 279 unique GUS enzymes organized into six categories based on active-site structural features. Because mice represent a model biomedical research organism, here we provide an analogous catalog of mouse intestinal microbial GUS proteins—a mouse gut GUSome. Using metagenome analysis guided by protein structure, we examined 2.5 million unique proteins from a comprehensive mouse gut metagenome created from several mouse strains, providers, housing conditions, and diets. We identified 444 unique GUS proteins and organized them into six categories based on active-site features, similarly to the human GUSome analysis. GUS enzymes were encoded by the major gut microbial phyla, including Firmicutes (60%) and Bacteroidetes (21%), and there were nearly 20% for which taxonomy could not be assigned. No differences in gut microbial gus gene composition were observed for mice based on sex. However, mice exhibited gus differences based on active-site features associated with provider, location, strain, and diet. Furthermore, diet yielded the largest differences in gus composition. Biochemical analysis of two low-fat-associated GUS enzymes revealed that they are variable with respect to their efficacy of processing both sulfated and nonsulfated heparan nonasaccharides containing terminal glucuronides. IMPORTANCE Mice are commonly employed as model organisms of mammalian disease; as such, our understanding of the compositions of their gut microbiomes is critical to appreciating how the mouse and human gastrointestinal tracts mirror one another. GUS enzymes, with importance in normal physiology and disease, are an attractive set of proteins to use for such analyses. Here we show that while the specific GUS enzymes differ at the sequence level, a core GUSome functionality appears conserved between mouse and human gastrointestinal bacteria. Mouse strain, provider, housing location, and diet exhibit distinct GUSomes and gus gene compositions, but sex seems not to affect the GUSome. These data provide a basis for understanding the gut microbial GUS enzymes present in commonly used laboratory mice. Further, they demonstrate the utility of metagenome analysis guided by protein structure to provide specific sets of functionally related proteins from whole-genome metagenome sequencing data.

Sign in / Sign up

Export Citation Format

Share Document