Did you mean: bacteroidetes
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Nature Dec 2006Two groups of beneficial bacteria are dominant in the human gut, the Bacteroidetes and the Firmicutes. Here we show that the relative proportion of Bacteroidetes is... (Clinical Trial)
Clinical Trial
Two groups of beneficial bacteria are dominant in the human gut, the Bacteroidetes and the Firmicutes. Here we show that the relative proportion of Bacteroidetes is decreased in obese people by comparison with lean people, and that this proportion increases with weight loss on two types of low-calorie diet. Our findings indicate that obesity has a microbial component, which might have potential therapeutic implications.
Topics: Adiposity; Animals; Bacteria; Bacteroidetes; Diet; Gastrointestinal Tract; Humans; Obesity; RNA, Ribosomal, 16S
PubMed: 17183309
DOI: 10.1038/4441022a -
Frontiers in Immunology 2020is a relatively new genus of bacteria isolated primarily from medical clinical samples, although at a low rate compared to other genus members of the phylum, which are... (Review)
Review
is a relatively new genus of bacteria isolated primarily from medical clinical samples, although at a low rate compared to other genus members of the phylum, which are highly relevant in dysbiosis and disease. According to the taxonomy database at The National Center for Biotechnology Information, the genus consists of 13 species: , and and , and the subspecies subspecies vulgaris (vs. subsp.) are the newest strains featured outside that list. Although typically isolated from the human gut microbiome various species of this genus have been isolated from patients suffering from appendicitis, and abdominal and rectal abscess. It is possible that as spp. emerge, their identification in clinical samples may be underrepresented as novel MS-TOF methods may not be fully capable to discriminate distinct species as separate since it will require the upgrading of MS-TOF identification databases. In terms of pathogenicity, there is contrasting evidence indicating that may have protective effects against some diseases, including liver fibrosis, colitis, cancer immunotherapy, and cardiovascular disease. In contrast, other studies indicate is pathogenic in colorectal cancer and is associated with mental signs of depression. Gut dysbiosis seems to play a role in determining the compositional abundance of in the feces (., in non-alcoholic steatohepatitis, hepatic encephalopathy, and liver fibrosis). Since is a relatively recent sub-branch genus of the phylum, and since are commonly associated with chronic intestinal inflammation, this narrative review illustrates emerging immunological and mechanistic implications by which spp. correlate with human health.
Topics: Animals; Bacteroidetes; Dysbiosis; Gastrointestinal Microbiome; Host-Pathogen Interactions; Humans; Inflammation; Intestines; Mental Disorders; Mental Health; Neoplasms
PubMed: 32582143
DOI: 10.3389/fimmu.2020.00906 -
Gut Microbes 2021is the type strain for the genus , a group of gram-negative anaerobic bacteria that commonly colonize the gastrointestinal tract of numerous species. First isolated in... (Review)
Review
is the type strain for the genus , a group of gram-negative anaerobic bacteria that commonly colonize the gastrointestinal tract of numerous species. First isolated in the 1930s from a clinical specimen as , the strain was re-classified to form the new genus in 2006. Currently, the genus consists of 15 species, 10 of which are listed as 'validly named' (, and ) and 5 'not validly named' (, and ) by the List of Prokaryotic names with Standing in Nomenclature. The genus has been associated with reports of both beneficial and pathogenic effects in human health. Herein, we review the literature on the history, ecology, diseases, antimicrobial resistance, and genetics of this bacterium, illustrating the effects of on human and animal health.
Topics: Animals; Anti-Bacterial Agents; Bacteroidetes; Drug Resistance, Bacterial; Gastrointestinal Microbiome; Gram-Negative Bacterial Infections; Humans; Phylogeny; Probiotics
PubMed: 34196581
DOI: 10.1080/19490976.2021.1922241 -
Journal of Bacteriology Aug 2017The complex carbohydrates of terrestrial and marine biomass represent a rich nutrient source for free-living and mutualistic microbes alike. The enzymatic... (Review)
Review
The complex carbohydrates of terrestrial and marine biomass represent a rich nutrient source for free-living and mutualistic microbes alike. The enzymatic saccharification of these diverse substrates is of critical importance for fueling a variety of complex microbial communities, including marine, soil, ruminant, and monogastric microbiota. Consequently, highly specific carbohydrate-active enzymes, recognition proteins, and transporters are enriched in the genomes of certain species and are of critical importance in competitive environments. In bacteria, these systems are organized as polysaccharide utilization loci (PULs), which are strictly regulated, colocalized gene clusters that encode enzyme and protein ensembles required for the saccharification of complex carbohydrates. This review provides historical perspectives and summarizes key findings in the study of these systems, highlighting a critical shift from sequence-based PUL discovery to systems-based analyses combining reverse genetics, biochemistry, enzymology, and structural biology to precisely illuminate the molecular mechanisms underpinning PUL function. The ecological implications of dynamic PUL deployment by key species in the human gastrointestinal tract are explored, as well as the wider distribution of these systems in other gut, terrestrial, and marine environments.
Topics: Bacteroidetes; Energy Metabolism; Gene Expression Regulation, Bacterial; Hydrolysis; Multigene Family; Polysaccharides
PubMed: 28138099
DOI: 10.1128/JB.00860-16 -
Proceedings of the National Academy of... Jan 2010Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other...
Porphyromonas gingivalis secretes strong proteases called gingipains that are implicated in periodontal pathogenesis. Protein secretion systems common to other Gram-negative bacteria are lacking in P. gingivalis, but several proteins, including PorT, have been linked to gingipain secretion. Comparative genome analysis and genetic experiments revealed 11 additional proteins involved in gingipain secretion. Six of these (PorK, PorL, PorM, PorN, PorW, and Sov) were similar in sequence to Flavobacterium johnsoniae gliding motility proteins, and two others (PorX and PorY) were putative two-component system regulatory proteins. Real-time RT-PCR analysis revealed that porK, porL, porM, porN, porP, porT, and sov were down-regulated in P. gingivalis porX and porY mutants. Disruption of the F. johnsoniae porT ortholog resulted in defects in motility, chitinase secretion, and translocation of a gliding motility protein, SprB adhesin, to the cell surface, providing a link between a unique protein translocation system and a motility apparatus in members of the Bacteroidetes phylum.
Topics: Adhesins, Bacterial; Animals; Bacterial Proteins; Bacteroidetes; Cell Movement; Chitinases; Cysteine Endopeptidases; Genome, Bacterial; Gingipain Cysteine Endopeptidases; Microarray Analysis; Molecular Sequence Data; Repressor Proteins
PubMed: 19966289
DOI: 10.1073/pnas.0912010107 -
Environmental Research Jul 2023Ruminant animals house a dense and diverse community of microorganisms in their rumen, an enlarged compartment in their stomach, which provides a supportive environment... (Review)
Review
Ruminant animals house a dense and diverse community of microorganisms in their rumen, an enlarged compartment in their stomach, which provides a supportive environment for the storage and microbial fermentation of ingested feeds dominated by plant materials. The rumen microbiota has acquired diverse and functionally overlapped enzymes for the degradation of plant cell wall polysaccharides. In rumen Bacteroidetes, enzymes involved in degradation are clustered into polysaccharide utilization loci to facilitate coordinated expression when target polysaccharides are available. Firmicutes use free enzymes and cellulosomes to degrade the polysaccharides. Fibrobacters either aggregate lignocellulose-degrading enzymes on their cell surface or release them into the extracellular medium in membrane vesicles, a mechanism that has proven extremely effective in the breakdown of recalcitrant cellulose. Based on current metagenomic analyses, rumen Bacteroidetes and Firmicutes are categorized as generalist microbes that can degrade a wide range of polysaccharides, while other members adapted toward specific polysaccharides. Particularly, there is ample evidence that Verrucomicrobia and Spirochaetes have evolved enzyme systems for the breakdown of complex polysaccharides such as xyloglucans, peptidoglycans, and pectin. It is concluded that diversity in degradation mechanisms is required to ensure that every component in feeds is efficiently degraded, which is key to harvesting maximum energy by host animals.
Topics: Animals; Metagenome; Rumen; Lignin; Bacteria; Polysaccharides; Bacteroidetes
PubMed: 37086884
DOI: 10.1016/j.envres.2023.115925 -
FEMS Microbiology Letters Jan 2015Cheese rinds host a specific microbiota composed of both prokaryotes (such as Actinobacteria, Firmicutes and Proteobacteria) and eukaryotes (primarily yeasts and... (Review)
Review
Cheese rinds host a specific microbiota composed of both prokaryotes (such as Actinobacteria, Firmicutes and Proteobacteria) and eukaryotes (primarily yeasts and moulds). By combining modern molecular biology tools with conventional, culture-based techniques, it has now become possible to create a catalogue of the biodiversity that inhabits this special environment. Here, we review the microbial genera detected on the cheese surface and highlight the previously unsuspected importance of non-inoculated microflora--raising the question of the latter's environmental sources and their role in shaping microbial communities. There is now a clear need to revise the current view of the cheese rind ecosystem (i.e. that of a well-defined, perfectly controlled ecosystem). Inclusion of these new findings should enable us to better understand the cheese-making process.
Topics: Bacteroidetes; Cheese; Food Microbiology; Fungi; Gram-Positive Bacteria; Microbiota; Proteobacteria; Yeasts
PubMed: 25670699
DOI: 10.1093/femsle/fnu015 -
Natural Product Reports Dec 2007New microbial sources of natural products are urgently needed in order to find new structural classes and/or unique structural variations. Gliding bacteria, as found in... (Review)
Review
New microbial sources of natural products are urgently needed in order to find new structural classes and/or unique structural variations. Gliding bacteria, as found in the taxa Chloroflexi, Proteobacteria, Bacteroidetes and Cyanobacteria, include members whose secondary metabolism is hardly investigated. Also, many of the members of these taxa have rather large genome sizes, pointing towards their potential to produce natural products. A general overview on the chemistry of gliding bacteria is currently hard to retrieve from the literature, and the compilation presented here is intended to highlight the metabolic versatility of these organisms.
Topics: Bacteroidetes; Biological Products; Chloroflexi; Cyanobacteria; Molecular Structure; Proteobacteria
PubMed: 18033578
DOI: 10.1039/b612668p -
Nihon Saikingaku Zasshi. Japanese... 2017
Review
Topics: Animals; Bacterial Proteins; Bacterial Secretion Systems; Bacteroidetes; Fimbriae, Bacterial; Genome, Bacterial; Humans
PubMed: 28239041
DOI: 10.3412/jsb.72.1 -
Gut Microbes 2011It is becoming increasingly clear that diet is one of the major factors that drives the function and composition of the intestinal microbiota. The diet of humans is... (Review)
Review
It is becoming increasingly clear that diet is one of the major factors that drives the function and composition of the intestinal microbiota. The diet of humans is highly diverse when considering different populations or even a single individual over a relatively short period of time. However, we are just beginning to understand the mechanisms that connect dietary change to intestinal microbiota dynamics. The community of microbes within our distal digestive tract influences numerous aspects of our biology, and aberrant shifts in its composition appear to be associated with several diseases. It is, therefore, necessary to understand how our behaviour and environmental factors, such as changes in diet, impact our intestinal residents. Here we look to recent work to highlight some of the major questions on the horizon for understanding the key role that the Bacteroidetes play in the commerce of dietary polysaccharides within the intestine.
Topics: Bacteroidetes; Gastrointestinal Tract; Humans; Models, Biological; Polysaccharides
PubMed: 21637023
DOI: 10.4161/gmic.2.2.15232