Did you mean: bacteroidetes
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World Journal of Gastroenterology Aug 2015Relation between the gut microbiota and human health is being increasingly recognised. It is now well established that a healthy gut flora is largely responsible for... (Review)
Review
Relation between the gut microbiota and human health is being increasingly recognised. It is now well established that a healthy gut flora is largely responsible for overall health of the host. The normal human gut microbiota comprises of two major phyla, namely Bacteroidetes and Firmicutes. Though the gut microbiota in an infant appears haphazard, it starts resembling the adult flora by the age of 3 years. Nevertheless, there exist temporal and spatial variations in the microbial distribution from esophagus to the rectum all along the individual's life span. Developments in genome sequencing technologies and bioinformatics have now enabled scientists to study these microorganisms and their function and microbe-host interactions in an elaborate manner both in health and disease. The normal gut microbiota imparts specific function in host nutrient metabolism, xenobiotic and drug metabolism, maintenance of structural integrity of the gut mucosal barrier, immunomodulation, and protection against pathogens. Several factors play a role in shaping the normal gut microbiota. They include (1) the mode of delivery (vaginal or caesarean); (2) diet during infancy (breast milk or formula feeds) and adulthood (vegan based or meat based); and (3) use of antibiotics or antibiotic like molecules that are derived from the environment or the gut commensal community. A major concern of antibiotic use is the long-term alteration of the normal healthy gut microbiota and horizontal transfer of resistance genes that could result in reservoir of organisms with a multidrug resistant gene pool.
Topics: Age Factors; Anti-Bacterial Agents; Bacteriological Techniques; Bacteroidetes; Computational Biology; Diet; Firmicutes; Gastrointestinal Microbiome; Health Status; Homeostasis; Host-Pathogen Interactions; Humans; Intestines; Prebiotics; Probiotics; Synbiotics
PubMed: 26269668
DOI: 10.3748/wjg.v21.i29.8787 -
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 2021Hypothalamic regulations of food intake are altered during obesity. The dopaminergic mesocorticolimbic system, responsible for the hedonic response to food intake, is... (Review)
Review
Hypothalamic regulations of food intake are altered during obesity. The dopaminergic mesocorticolimbic system, responsible for the hedonic response to food intake, is also affected. Gut microbes are other key players involved in obesity. Therefore, we investigated whether the gut microbiota plays a causal role in hedonic food intake alterations contributing to obesity. We transferred fecal material from lean or diet-induced obese mice into recipient mice and evaluated the hedonic food intake using a food preference test comparing the intake of control and palatable diets (HFHS, High-Fat High-Sucrose) in donor and recipient mice. Obese mice ate 58% less HFHS during the food preference test ( < 0.0001) than the lean donors, suggesting a dysregulation of the hedonic food intake during obesity. Strikingly, the reduction of the pleasure induced by eating during obesity was transferable through gut microbiota transplantation since obese gut microbiota recipient mice exhibited similar reduction in HFHS intake during the food preference test (40% reduction as compared to lean gut microbiota recipient mice, < 0.01). This effect was associated with a consistent trend in modifications of dopaminergic markers expression in the striatum. We also pinpointed a highly positive correlation between HFHS intake and ( < 0.0001), which could represent a potential actor involved in hedonic feeding probably through the gut-to-brain axis. We further demonstrated the key roles played by gut microbes in this paradigm since depletion of gut microbiota using broad-spectrum antibiotics also altered HFHS intake during food preference test in lean mice. In conclusion, we discovered that gut microbes regulate hedonic aspects of food intake. Our data demonstrate that gut microbiota modifications associated with obesity participate in dysregulations of the reward and hedonic components of the food intake. These data provide evidence that gut microbes could be an interesting therapeutic target to tackle hedonic disorders related to obesity.
Topics: Animals; Bacteroidetes; Brain-Gut Axis; Corpus Striatum; Diet, High-Fat; Fecal Microbiota Transplantation; Feeding Behavior; Food Preferences; Gastrointestinal Microbiome; Hyperphagia; Male; Mice; Mice, Inbred C57BL; Obesity; Reward
PubMed: 34424831
DOI: 10.1080/19490976.2021.1959242 -
Science (New York, N.Y.) May 2009Human skin is a large, heterogeneous organ that protects the body from pathogens while sustaining microorganisms that influence human health and disease. Our analysis of...
Human skin is a large, heterogeneous organ that protects the body from pathogens while sustaining microorganisms that influence human health and disease. Our analysis of 16S ribosomal RNA gene sequences obtained from 20 distinct skin sites of healthy humans revealed that physiologically comparable sites harbor similar bacterial communities. The complexity and stability of the microbial community are dependent on the specific characteristics of the skin site. This topographical and temporal survey provides a baseline for studies that examine the role of bacterial communities in disease states and the microbial interdependencies required to maintain healthy skin.
Topics: Actinobacteria; Adult; Bacteria; Bacteroidetes; Biodiversity; Female; Genes, rRNA; Humans; Male; Metagenome; Molecular Sequence Data; Phylogeny; Proteobacteria; RNA, Ribosomal, 16S; Skin; Time Factors; Young Adult
PubMed: 19478181
DOI: 10.1126/science.1171700 -
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 -
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 -
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 -
The Journal of Endocrinology Mar 2023The human body is inhabited by numerous bacteria, fungi, and viruses, and each part has a unique microbial community structure. The gastrointestinal tract harbors... (Review)
Review
The human body is inhabited by numerous bacteria, fungi, and viruses, and each part has a unique microbial community structure. The gastrointestinal tract harbors approximately 100 trillion strains comprising more than 1000 bacterial species that maintain symbiotic relationships with the host. The gut microbiota consists mainly of the phyla Firmicutes, Bacteroidetes, Proteobacteria, and Actinobacteria. Of these, Firmicutes and Bacteroidetes constitute 70-90% of the total abundance. Gut microbiota utilize nutrients ingested by the host, interact with other bacterial species, and help maintain healthy homeostasis in the host. In recent years, it has become increasingly clear that a breakdown of the microbial structure and its functions, known as dysbiosis, is associated with the development of allergies, autoimmune diseases, cancers, and arteriosclerosis, among others. Metabolic diseases, such as obesity and diabetes, also have a causal relationship with dysbiosis. The present review provides a brief overview of the general roles of the gut microbiota and their relationship with metabolic disorders.
Topics: Humans; Gastrointestinal Microbiome; Dysbiosis; Bacteria; Gastrointestinal Tract; Bacteroidetes
PubMed: 36458804
DOI: 10.1530/JOE-22-0111 -
Environmental Microbiology Oct 2022Bacteria within the phylum Bacteroidota (Bacteroidetes) are known to cause devastating and widespread disease outbreaks in marine eukaryotic hosts. However, with few... (Review)
Review
Bacteria within the phylum Bacteroidota (Bacteroidetes) are known to cause devastating and widespread disease outbreaks in marine eukaryotic hosts. However, with few pathogens described in detail, their prevalence and virulence strategies remain largely unknown. Here, we systematically reviewed the literature to evaluate the current understanding of Bacteroidota that cause disease in marine hosts. Isolates affiliated with the genera Tenacibaculum and Aquimarina (Flavobacteriaceae) were the most widely reported and characterized pathogens. Although cultured isolates were predominantly Flavobacteriia, culture-independent studies also found classes Bacteroidia, Cytophagia and Sphingobacteriia associated with disease. We found that pathogenic marine Bacteroidota largely conformed to an opportunistic lifestyle but could also act as secondary pathogens or were involved in polymicrobial diseases. Many diseases were also associated with an environmental stressor, especially those affecting coral, macroalgae and fish. Key virulence traits included the production of adhesins and host tissue-degrading enzymes. Overall, the nature of disease involving Bacteroidota pathogens appears to be an outcome of complex host-pathogen-environment interactions; however, our understanding of virulence remains limited by the lack of functional characterization studies. This is concerning as Bacteroidota have the potential to emerge as a serious threat to marine ecosystems and aquaculture industries, driven by global changes in ocean conditions.
Topics: Animals; Anthozoa; Ecosystem; Fish Diseases; Flavobacteriaceae; Oceans and Seas; Tenacibaculum
PubMed: 35706128
DOI: 10.1111/1462-2920.16094 -
Science (New York, N.Y.) Nov 2023Nutrient starvation of beneficial bacteria helps them colonize the human gut.
Nutrient starvation of beneficial bacteria helps them colonize the human gut.
Topics: Humans; Symbiosis; Gastrointestinal Microbiome; Firmicutes; Bacteroidetes; Probiotics; Animals; Mice; Genetic Fitness; Genetic Engineering; Diet; Intestines; Gastrointestinal Diseases
PubMed: 37972163
DOI: 10.1126/science.adh9165