WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions, filtered to microbe.
A Gram-negative, obligate anaerobic genus within the Bacteroidetes phylum (family Rikenellaceae). Alistipes occupies a complex and context-dependent role in the gut ecosystem — some species carry well-documented anti-inflammatory properties, while the genus is paradoxic…
A genus of Gram-positive obligate anaerobes in the family Lachnospiraceae (Clostridium cluster XIVa) that occupy a critical metabolic relay position in gut ecosystem stability: converting lactate to butyrate. Anaerostipes is one of the most consistently depleted genera …
A Gram-positive, obligate anaerobic genus within the Firmicutes phylum (family Oscillospiraceae or Ruminococcaceae depending on classification) that possesses a unique metabolic capability: butyrate production from lysine fermentation rather than from dietary fiber. Thi…
Roseburia intestinalis is a Gram-positive, obligate anaerobic member of the Lachnospiraceae family (Firmicutes). It is one of the most important butyrate producers in the human colon, converting dietary fiber into butyrate — the primary energy source for colonocytes and…
The causative agent of plague -- one of the most devastating infectious diseases in human history and a modern bioterrorism concern (Tier 1 Select Agent). Y. pestis depends on nickel for glyoxalase I-mediated metabolic detoxification and produces the archetypal dual-fun…
A Gram-negative, obligate anaerobic genus within the family veillonellaceae (class Negativicutes, phylum Firmicutes) defined by its specialized amino acid fermentation -- the genus name literally means "acid from amino acids." Acidaminococcus ferments glutamate as its p…
A Gram-negative, aerobic, non-fermenting coccobacillus and a member of the ESKAPE group of priority pathogens (Enterococcus, Staphylococcus, Klebsiella, Acinetobacter, Pseudomonas, Enterobacter). Acinetobacter baumannii is among the most problematic nosocomial pathogens…
A genus of Gram-positive, facultatively anaerobic, filamentous bacteria that are among the most abundant colonizers of the human oral cavity. Actinomyces species, particularly A. naeslundii, play dual roles as early dental plaque colonizers and as opportunistic pathogen…
A pathotype of escherichia coli that adheres to and invades intestinal epithelial cells, survives and replicates within macrophages, and is strongly associated with ileal Crohn's disease. Unlike classical diarrheagenic E. coli pathotypes (EPEC, ETEC, EHEC), AIEC does no…
Aeromonas is a genus of Gram-negative, facultatively anaerobic bacteria found in aquatic environments and, increasingly recognized as an opportunistic gut pathogen. Several species — particularly Aeromonas hydrophila, A. veronii, and A. caviae — are associated with gast…
A Gram-negative, obligate anaerobic, mucin-degrading bacterium that colonizes the intestinal mucus layer and has emerged as one of the most important next-generation probiotics. A. muciniphila is consistently depleted in disease states associated with metal dyshomeostas…
Alloprevotella is a genus of Gram-negative, obligate anaerobic bacteria within the family Prevotellaceae that represents a distinct clade from prevotella with specific protective roles in type 2 diabetes prevention and metabolic health. Alloprevotella depletion is one o…
Anaerococcus is a genus of Gram-positive, obligate anaerobic cocci within the phylum Firmicutes. It is a normal inhabitant of the human vaginal, skin, and gastrointestinal microbiota, but is recognized as an opportunistic pathogen in dysbiotic states, particularly when …
A ubiquitous filamentous fungal genus that is both an environmental saprophyte and an opportunistic human pathogen. A. fumigatus is the primary cause of invasive aspergillosis in immunocompromised patients, while A. niger is relevant to food contamination. The genus is …
A Gram-positive, aerobic to facultatively anaerobic, spore-forming genus that bridges environmental and human microbiology. The genus encompasses both beneficial species (B. subtilis, B. coagulans as probiotics) and pathogens (B. cereus causing food poisoning, B. anthra…
Bacteroides is the most abundant genus in the Western adult gut and a cornerstone of intestinal polysaccharide metabolism. As members of the bacteroidetes phylum, Bacteroides species encode enormous repertoires of carbohydrate-active enzymes (CAZymes) organized into pol…
Bacteroides caccae is a Gram-negative, obligate anaerobic member of the bacteroidetes phylum and a common fiber-degrading commensal in the human colon. While less individually prominent than bacteroides fragilis or bacteroides thetaiotaomicron, B. caccae has emerged as …
Bacteroides thetaiotaomicron is one of the most abundant and metabolically versatile commensals of the human gut, routinely cited as a model organism for studying host-microbe symbiosis. Its genome was one of the first human gut bacterial genomes fully sequenced, and su…
A Gram-negative obligate anaerobe that exemplifies the commensal-pathobiont spectrum. B. vulgatus is a common component of the healthy gut microbiota, yet is significantly enriched in colorectal cancer and depression, suggesting a context-dependent pathogenic potential.…
Bacteroidetes (recently reclassified as Bacteroidota) is one of the two dominant bacterial phyla in the human gut, together with firmicutes typically comprising 90% of the intestinal microbiota. Bacteroidetes are Gram-negative, obligately anaerobic, non-spore-forming ro…
A class of Gram-negative bacteria within the phylum Proteobacteria that has emerged as a causal risk factor for schizophrenia and bipolar disorder through Mendelian randomization studies. Betaproteobacteria includes genera with notable metal tolerance -- particularly wi…
A genus of Gram-positive, obligate anaerobic bacteria that dominate the infant gut microbiome and remain important commensals throughout life. Bifidobacterium species are distinctive in the metallomics context because some species possess Ni-dependent urease -- an unusu…
Bifidobacterium adolescentis is a Gram-positive, obligate anaerobic species within the phylum Actinobacteria and the dominant Bifidobacterium species in the adult human gut. It is a specialist degrader of resistant starch and dietary fiber, producing acetate and lactate…
Bifidobacterium breve is a Gram-positive, obligate anaerobic species within the phylum Actinobacteria, predominantly found in the infant gut and breast milk. It is among the earliest colonizers of the neonatal intestine and plays a key role in human milk oligosaccharide…
Bifidobacterium longum is a Gram-positive, obligate anaerobic bacterium and one of the most important commensal species in human health from infancy through old age. Its subspecies — B. longum subsp. longum (adult gut), B. longum subsp. infantis (infant gut, HMO degrade…
A genus of Gram-negative intracellular pathogens causing brucellosis, the most common bacterial zoonosis worldwide. Brucella species depend on nickel-activated urease for gastrointestinal survival during the initial phase of infection, and urease immunization has been s…
A Gram-negative, obligate anaerobic genus within the Bacteroidetes phylum (family Odoribacteraceae). Despite its relatively recent characterization, Butyricimonas has gained significant attention as a member of the protective butyrate-producing consortium that is consis…
The leading bacterial cause of diarrheal disease worldwide, with an estimated 400-500 million cases annually. C. jejuni is notable in the metallomics context for possessing a nickel-dependent [NiFe] hydrogenase essential for colonization but lacking urease -- a striking…
An opportunistic fungal pathogen whose relationship with metals is multifaceted: C. albicans can biosorb heavy metals from its environment, heavy metal exposure promotes its virulence in immunocompromised hosts, and metal nanoparticles are being developed as antifungal …
Candida tropicalis is an opportunistic fungal pathogen and occasional gut commensal, increasingly recognized as one of the most clinically significant non-albicans Candida (NAC) species. Once considered a distant runner-up to C. albicans, it has emerged as a major drive…
Candidozyma auris is the current name for NCBITaxon:498019. Liu and colleagues established the combination in 2024 as MycoBank MB 848169; Candida auris Satoh & Makimura 2009 is its basionym, not a separate species ncbi taxonomy candidozyma auris index fungorum candidozy…
Chlamydia is a genus of obligate intracellular, Gram-negative bacteria with a unique biphasic developmental cycle. The genus includes three species pathogenic to humans: chlamydia trachomatis (STI and trachoma), C. pneumoniae (respiratory infections, atherosclerosis ass…
Chlamydia trachomatis is a Gram-negative, obligate intracellular bacterium and the most common bacterial sexually transmitted infection worldwide. Its biphasic developmental cycle — alternating between the infectious elementary body (EB) and the replicative reticulate b…
Citrobacter is a genus of Gram-negative, facultatively anaerobic bacteria in the Enterobacteriaceae family, named for its ability to utilize citrate as a sole carbon source. Species include C. freundii, C. koseri, and C. rodentium (a mouse model for EHEC infection). In …
Clostridioides difficile is the current NCBI name for NCBITaxon:1496 and the correct, medically recommended combination recorded by LPSN. Both records retain Clostridium difficile as a validly published homotypic synonym of the same organism rather than a separate speci…
A large, polyphyletic genus of Gram-positive, obligate anaerobic, spore-forming bacteria encompassing both critical beneficial commensals and dangerous pathogens. Former Clostridium clusters IV and XIVa are now reclassified into ruminococcus-family Ruminococcaceae and l…
Clostridium perfringens is a Gram-positive, strictly anaerobic, spore-forming bacterium infamous for causing gas gangrene, food poisoning, and necrotizing enterocolitis (NEC) in premature infants. It is one of the most widely distributed pathogenic bacteria in nature, f…
Clostridium symbiosum is a Gram-positive, obligately anaerobic bacterium within the Clostridium cluster XIVa — a taxonomic group enriched for short-chain fatty acid (SCFA) producers and specialized bile acid metabolizers. Despite its ambiguous name (suggesting symbiotic…
Corynebacterium is a large genus of Gram-positive, club-shaped bacteria with over 130 species spanning commensals, opportunistic pathogens, and the classic pathogen C. diphtheriae. In the WikiBiome context, Corynebacterium is most notable for its dominance in the male r…
An encapsulated basidiomycete yeast that causes cryptococcal meningitis -- the leading cause of meningitis in HIV/AIDS patients and responsible for an estimated 180,000 deaths annually. Its nickel-dependent urease has been called the organism's "Achilles' heel" because …
Debaryomyces is a genus of ascomycetous fungi, with D. hansenii being the most clinically relevant species, that represents a prominent opportunistic pathobiont enriched in inflammatory bowel disease, particularly crohns disease. Unlike many commensal fungi, Debaryomyce…
An order of Gram-negative, strictly anaerobic sulfate-reducing bacteria (SRB) within the class Deltaproteobacteria. The defining metabolic feature of Desulfovibrionales is dissimilatory sulfate reduction -- using sulfate as a terminal electron acceptor and producing hyd…
Dialister is a genus of Gram-negative, obligate anaerobic bacteria within the family Veillonellaceae that represents one of the strongest protective associations in gut-brain-axis research. Dialister depletion is a consistent and independent biomarker of depression, anx…
A Gram-positive, obligate anaerobic genus within the lachnospiraceae family (Firmicutes phylum). Dorea occupies a mixed role in the gut ecosystem -- while it is a core member of the healthy human microbiome, several species are consistently enriched in autoimmune and ne…
Eggerthella is a genus of Gram-positive, strictly anaerobic, non-spore-forming bacteria in the family Eggerthellaceae (phylum Actinobacteria). The most studied species, Eggerthella lenta, was originally classified as Eubacterium lentum before reclassification. It is a n…
A Gram-positive obligate anaerobe and key estrobolome member that links metabolic dysbiosis to hormone-driven diseases, particularly endometriosis. E. lenta is remarkable for its ability to inactivate cardiac glycosides (like digoxin) and to produce beta-glucuronidase, …
Enterobacter is a genus of Gram-negative, facultatively anaerobic bacteria in the enterobacteriaceae family. Key species include enterobacter cloacae (the most clinically relevant) and E. hormaechei. Like other Enterobacteriaceae, Enterobacter possesses iron-dependent s…
Enterobacter cloacae is a Gram-negative, facultatively anaerobic member of the Enterobacteriaceae. Ubiquitous in soil, water, and the mammalian gut, it is a leading cause of nosocomial infections and carries clinically significant antibiotic resistance through inducible…
A family of Gram-negative, facultative anaerobic Gammaproteobacteria that includes many of the most important human pathogens: escherichia coli, klebsiella pneumoniae, salmonella typhimurium, shigella flexneri, yersinia pestis, proteus mirabilis, Morganella, and Serrati…
Enterococcus faecalis is a Gram-positive, facultatively anaerobic coccus that inhabits the gastrointestinal tract, oral cavity, and genitourinary tract of humans. It is a commensal in the healthy gut at low abundance but is one of the most clinically significant opportu…
Erysipelotrichaceae is a family within the phylum Firmicutes that has drawn increasing attention for its consistent enrichment in metabolic disorders. Members of this family are Gram-positive, obligate anaerobes found throughout the mammalian gastrointestinal tract, whe…
The most abundant bacterium in the healthy human colon (5-15% of total fecal microbiota), F. prausnitzii is the premier butyrate producer in the gut and a cornerstone of anti-inflammatory intestinal homeostasis. Its depletion is one of the most consistent microbiome sig…
Finegoldia is a genus of Gram-positive, strictly anaerobic cocci, with Finegoldia magna as the primary species of clinical relevance. Formerly classified within Peptostreptococcus, this organism inhabits mucosal surfaces including the vaginal, skin, and gastrointestinal…
Firmicutes (recently reclassified as Bacillota) is the dominant bacterial phylum in the Western adult gut, comprising the core community of short-chain fatty acid (SCFA) producers that maintain intestinal barrier integrity, regulate immune function, and influence system…
Fusicatenibacter is a Gram-positive obligate anaerobic genus within the Lachnospiraceae (Firmicutes). The primary species, F. saccharivorans, was isolated from human feces and is recognized as a beneficial commensal that produces butyrate and modulates intestinal immune…
An order of Gram-negative, obligate anaerobic bacteria within the phylum Fusobacteriota (formerly Fusobacteria). This order-level page covers the broader taxonomic group that includes the well-characterized genus fusobacterium and its key species fusobacterium nucleatum…
A Gram-negative obligate anaerobe that has emerged as a major pathogen in colorectal cancer (CRC) and inflammatory bowel disease. F. nucleatum is significantly enriched in CRC tissue and tumors compared to healthy mucosa, making it one of the strongest microbe-cancer as…
A Gram-negative obligate anaerobe that occupies a paradoxical niche in the gut microbiota: as a weak butyrate producer (short-chain fatty acid), it has anti-inflammatory potential; as a virulent invasive pathobiont in inflammatory bowel disease (particularly ulcerative …
See also the genus page: gardnerella Gardnerella vaginalis is the primary causative agent of bacterial vaginosis (BV), the most common vaginal infection worldwide. This species page focuses on the species-level biology — particularly the vaginolysin cytotoxin and biofil…
Gemella is a genus of Gram-positive, facultatively anaerobic cocci that are normal commensals of the oral cavity. Species include G. morbillorum, G. haemolysans, and G. sanguinis. In the WikiBiome context, Gemella is notable for its oral-gut translocation pattern — an o…
Haemophilus is a genus of small, Gram-negative, facultatively anaerobic coccobacilli that inhabit the upper respiratory tract, oral cavity, and gastrointestinal tract. The genus name literally means "blood-loving" -- a direct reference to its absolute requirement for he…
A Gram-negative, microaerophilic bacterium within the Epsilonproteobacteria (family Helicobacteraceae) that is the primary murine model of hepatobiliary and intestinal disease. Unlike its more famous relative helicobacter pylori, which colonizes the stomach, H. hepaticu…
Klebsiella is a genus of Gram-negative, encapsulated, facultatively anaerobic bacteria in the Enterobacteriaceae family. With 141 file mentions across the vault, Klebsiella is one of the most frequently referenced opportunistic pathogens. The dominant species is klebsie…
A Gram-negative opportunistic pathogen and member of the ESKAPE group of antibiotic-resistant priority pathogens. K. pneumoniae deploys multiple nickel-dependent enzymes for virulence and relies on the dual-function metallophore yersiniabactin for both iron and nickel s…
Lachnoclostridium is a genus of obligate anaerobic, Gram-positive bacteria in the lachnospiraceae family. It is a butyrate-producing commensal with emerging clinical significance as a treatment response biomarker and diagnostic marker.
A family within the Firmicutes phylum (order Clostridiales, formerly Clostridium cluster XIVa) that serves as a sentinel indicator of gut health -- its depletion is the single most consistent microbiome signature across nearly every disease represented in this wiki. The…
This page serves as the family-level hub for Lachnospiraceae, connecting the individual genus and species pages (roseburia, blautia, anaerostipes, agathobacter rectalis) with the overarching ecological and metabolic framework that defines the family. For the primary ent…
Lactobacillus iners is a Gram-positive, facultatively anaerobic bacterium that dominates the vaginal microbiome of many women worldwide, defining Community State Type III (CST-III) in vaginal microbiome classification. For decades, all vaginal Lactobacillus species were…
Lactobacillus rhamnosus is a Gram-positive, facultatively anaerobic lactic acid bacterium and one of the most extensively studied probiotic species. The GG strain (ATCC 53103), isolated from a healthy human intestinal tract by Gorbach and Goldin in 1983, is the single m…
Lancefieldella parvula is the current name for NCBITaxon:1382. Atopobium parvulum is a validly published historical homotypic synonym rather than the current canonical name ncbi taxonomy lancefieldella parvula lpsn lancefieldella parvula.
A Gram-negative obligate anaerobe traditionally considered an oral commensal, but increasingly recognized as an opportunistic pathobiont with the ability to translocate from oral biofilms to the gastrointestinal tract and bloodstream. Leptotrichia species are prominentl…
A Gram-positive, obligate anaerobic genus within the family lachnospiraceae (phylum Firmicutes) that was recently reclassified from Ruminococcus based on phylogenomic evidence. The key species Mediterraneibacter faecis (formerly Ruminococcus gnavus clade relatives) is a…
Megamonas is a genus of obligate anaerobic, Gram-negative bacteria in the family Veillonellaceae (class Negativicutes, phylum Firmicutes). The type species is Megamonas hypermegale, with M. funiformis also well-characterized. It is a common member of the human gut micro…
Megasphaera is a genus of obligate anaerobic, Gram-negative bacteria in the family Veillonellaceae (class Negativicutes, phylum Firmicutes). The genus occupies two distinct ecological niches — the vaginal microbiome (where it is a hallmark of bacterial vaginosis) and th…
The only archaeon represented in this wiki -- Methanobrevibacter smithii is the dominant methane-producing microorganism in the human gut, belonging to the domain Archaea rather than Bacteria. As a hydrogenotrophic methanogen, it converts H2 + CO2 into methane (CH4), pl…
A class of bacteria within the phylum Tenericutes defined by the complete absence of a cell wall -- the smallest self-replicating organisms known, with minimal genomes (580 kb-1.4 Mb). While Mollicutes are best known through their pathogenic members (Mycoplasma pneumoni…
Morganella morganii is a Gram-negative, facultatively anaerobic rod belonging to the family Morganellaceae (formerly classified within Enterobacteriaceae). It inhabits the human gastrointestinal tract as a low-abundance commensal but becomes an opportunistic pathogen in…
Mortierella is a genus of soil-dwelling fungi in the phylum Mortierellomycota (formerly placed in Zygomycota). While primarily known as environmental saprotrophs, Mortierella species have recently been identified as residents of the human gut mycobiome -- the fungal com…
Mycoplasma is a genus of wall-less bacteria in the class Mollicutes, characterized by the smallest genomes of any self-replicating organisms (~580–1,350 kb). The lack of a cell wall makes them intrinsically resistant to beta-lactam antibiotics and undetectable by Gram s…
See also: mycoplasma (genus page) Mycoplasma hominis is a wall-less bacterium in the class Mollicutes that colonizes the urogenital tract. It is associated with bacterial vaginosis, pelvic inflammatory disease, and neonatal infections.