WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions.
Arachidonic acid (AA) is a 20-carbon omega-6 polyunsaturated fatty acid (20:4n-6) that serves as the primary substrate for prostaglandin and leukotriene synthesis via COX-2 and 5-LOX pathways. It is the dominant pro-inflammatory lipid mediator — and its balance with ant…
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…
Bifidobacteriaceae is the family containing bifidobacterium and related genera (alloscardovia). It is the dominant family in the healthy infant gut and a significant commensal family in adults. Family-level depletion is documented in ASD (marked reduction of Actinobacte…
Bifidobacteriales is an order of Gram-positive, strictly anaerobic bacteria within the phylum Actinobacteria. The order contains the family Bifidobacteriaceae, which includes the genus Bifidobacterium — among the most widely studied probiotic organisms and a hallmark of…
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 bifidum is an obligate anaerobic, Gram-positive species that specializes in human milk oligosaccharide (HMO) and mucin glycan degradation. It is one of the earliest colonizers of the infant gut and a widely used probiotic species.
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…
Bifidobacterium longum subsp. infantis is the current, validly published name for NCBITaxon:1682. Bifidobacterium infantis Reuter 1963 is its basionym, not a separate current species ncbi taxonomy bifidobacterium longum subsp infantis lpsn bifidobacterium longum subsp i…
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…
Lactobacillus acidophilus is one of the most widely used probiotic species, with clinical trial evidence spanning multiple conditions. It is a component of many multi-strain probiotic formulations and has been tested in RCTs for schizophrenia, breast cancer chemotherapy…
Peptidoglycan (murein) is the polymer of N-acetylglucosamine and N-acetylmuramic acid cross-linked by short peptides that forms the bacterial cell wall. It is a major pathogen-associated molecular pattern (PAMP) recognized by host TLR2 (intact peptidoglycan), NOD1 (meso…
Research summary — not medical advice. This page synthesizes published research on a mechanism-level intervention. It is not a clinical recommendation. Consult a qualified healthcare provider before making any changes to diet, supplementation, or treatment.
Acetate (acetic acid, C2) is the most abundant SCFA in the colon (~60% of total SCFAs) and the primary cross-feeding substrate for butyrate production. Produced by Bacteroides, Bifidobacterium, Prevotella, and acetogens from dietary fiber fermentation, acetate reaches p…
Actinobacteria (reclassified as Actinomycetota in 2021) is a major Gram-positive, high-GC-content bacterial phylum with remarkable ecological breadth. In the gut, it typically comprises 1-10% of the community -- a distant third behind firmicutes and bacteroidetes -- but…
Alloscardovia is a genus of anaerobic, Gram-positive bacteria in the family Bifidobacteriaceae (phylum Actinobacteria). The primary species is A. omnicolens, which colonizes the human urogenital tract. In the WikiBiome vault, Alloscardovia appears exclusively in endomet…
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…
Barnesiella is a validly published genus of Gram-negative, obligately anaerobic bacteria in the phylum Bacteroidota and family Barnesiellaceae. NCBI Taxonomy assigns the genus NCBITaxon:397864, and LPSN lists Barnesiella Sakamoto et al. 2007 as the correct name ncbi tax…
Bile salt hydrolase (BSH) is the microbial enzyme that deconjugates primary bile acids (taurocholate, glycocholate) by cleaving the amino acid (taurine or glycine) from the steroid core. This is the first and rate-limiting step in microbial bile acid transformation — wi…
Breast milk is the most effective single intervention for NEC prevention. Human milk oligosaccharides (HMOs) — the third most abundant component of breast milk — are selectively metabolized by Bifidobacteria, establishing the protective neonatal microbiome. Formula-fed …
Cyclooxygenase-2 (COX-2) is the inducible enzyme that converts arachidonic acid to prostaglandin H₂ — the precursor of prostaglandin E₂ (PGE₂), prostacyclin, and thromboxane. Unlike COX-1 (constitutive, homeostatic), COX-2 is transcriptionally induced by nf kappa b duri…
Depression is the most prevalent mental health disorder globally, affecting over 280 million people zhu 2025 microbiota gut brain axis depression review, and one of the most metal-sensitive conditions in this wiki. It sits at the convergence of nearly every pathway cata…
Estrogen recirculation is the recycling loop by which conjugated estrogens excreted in bile are deconjugated by gut bacterial beta glucuronidase, reabsorbed across the intestinal epithelium, and returned to systemic circulation uzuner 2023 bidirectional relationship end…
Fibromyalgia (FM) is a chronic pain syndrome affecting 2-4% of the global population Heidari et al. 2017, characterized by widespread musculoskeletal pain, fatigue, cognitive dysfunction ("fibro fog"), and sleep disturbances. Conventionally attributed to central sensiti…
Gamma-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the central nervous system. In the WikiBiome context, GABA is notable because gut bacteria produce it — certain Lactobacillus and Bifidobacterium species possess glutamate decarboxylase (GAD) e…
Alphabetical definitions of specialist terms used throughout this wiki. Where a full concept page exists, the term links to it. --- AhR (aryl hydrocarbon receptor) -- A ligand-activated transcription factor that senses microbial metabolites (especially indoles from tryp…
Graves' disease (GD) is an autoimmune thyroid disorder characterized by TSH receptor antibodies (TRAb) that stimulate the thyroid gland, causing hyperthyroidism kahaly 2022 graves disease targeted therapy review. It is the most common cause of hyperthyroidism, with conc…
Gut barrier dysfunction -- colloquially "leaky gut" -- is the pathological increase in intestinal permeability that permits translocation of bacteria, bacterial products (LPS, peptidoglycan), metals, and dietary antigens from the gut lumen into the systemic circulation.…
Human milk oligosaccharides are a diverse family of over 200 structurally distinct complex sugars found in breast milk. They are the third most abundant solid component of human milk (after lactose and lipids), yet they are not digestible by the infant. Their sole purpo…
Interferon gamma (IFN-γ) is the signature Th1 cytokine and the primary activator of macrophage antimicrobial functions. In the WikiBiome framework, IFN-γ is critical for two reasons: it drives nutritional immunity (iron restriction against intracellular pathogens) and i…
Kynurenine is the primary metabolite of the kynurenine pathway, which handles ~95% of tryptophan catabolism in the body. While serotonin gets more attention, the kynurenine pathway is quantitatively dominant -- and its downstream metabolites span the range from neuropro…
The kynurenine pathway (KP) is the dominant route of tryptophan catabolism, accounting for approximately 95% of dietary tryptophan degradation. It produces a cascade of neuroactive, immunomodulatory, and potentially neurotoxic metabolites whose balance determines whethe…
Lactobacillaceae is the family containing the genus lactobacillus and related genera. It is the dominant family in the healthy vaginal microbiome and a significant family in the gut. Family-level depletion is reported across schizophrenia szeligowski 2020 gut microbiome…
Research summary — not medical advice. This page synthesizes published research on a mechanism-level intervention. It is not a clinical recommendation. Consult a qualified healthcare provider before making any changes to diet, supplementation, or treatment.
Mendelian randomization (MR) is a statistical method that uses genetic variants as instrumental variables to infer causal relationships between an exposure (e.g., gut microbiome composition) and an outcome (e.g., disease). Because genetic variants are randomly allocated…
Metformin is a biguanide antihyperglycemic drug and the most widely prescribed medication for type 2 diabetes worldwide (~150 million users). While traditionally understood to work through hepatic AMPK activation and gluconeogenesis suppression, landmark studies have de…
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…
Necrotizing enterocolitis (NEC) is the most common and lethal gastrointestinal emergency in premature infants, affecting 5-12% of very low birth weight neonates (<1500 g) with mortality rates of 20-30%. Characterized by intestinal inflammation, necrosis, and perforation…
Odoribacter splanchnicus is a Gram-negative, obligate anaerobic bacterium belonging to the family Odoribacteraceae within the phylum Bacteroidota (formerly Bacteroidetes). It is a commensal resident of the human colon recognized primarily as a producer of short chain fa…
Omega-3 fatty acids — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — are anti-inflammatory polyunsaturated fatty acids that counterbalance the pro-inflammatory effects of omega-6 arachidonic acid. They act through multiple mechanisms: competitive COX-2/5-L…
A Gram-negative, obligate anaerobic genus within the phylum Bacteroidota (formerly Bacteroidetes) that was recently reclassified from Bacteroides based on phylogenomic evidence (Garcia-Lopez et al., 2019). The key species -- Phocaeicola vulgatus (formerly Bacteroides vu…
Polyunsaturated fatty acids (PUFAs) are fatty acids with multiple double bonds, divided into omega-3 (EPA, DHA, ALA) and omega-6 (arachidonic acid, linoleic acid) families. The omega-6:omega-3 ratio determines inflammatory tone — Western diets (~15:1) favor pro-inflamma…
Postpartum depression (PPD) affects 10-20% of women after delivery, with profound consequences for maternal health, infant bonding, and child neurodevelopment chao 2025 microbiota gut brain perinatal depression. The standard framing centers on hormonal withdrawal (estro…
Non-digestible food substrates that selectively stimulate the growth and/or activity of beneficial gut microorganisms, conferring health benefits to the host. Distinct from probiotics (live organisms) and postbiotics (microbial metabolic products), prebiotics act as fue…
Research summary — not medical advice. This page synthesizes published research on a mechanism-level intervention. It is not a clinical recommendation. Consult a qualified healthcare provider before making any changes to diet, supplementation, or treatment.
Premenstrual Dysphoric Disorder (PMDD) affects 3-8% of menstruating individuals Epperson et al. 2012, causing severe mood disturbances, irritability, anxiety, and physical symptoms during the luteal phase of the menstrual cycle. Distinguished from premenstrual syndrome …
A family of Gram-negative, obligate anaerobic bacteria within the phylum Bacteroidota (formerly Bacteroidetes) that includes the genus prevotella and the recently described alloprevotella. Prevotellaceae are specialist fiber fermenters producing short-chain fatty acids,…
Multi-strain probiotic supplementation with L. acidophilus, B. longum, and B. bifidum has shown promise in slowing CKD progression through anti-inflammatory mechanisms, though its effect on uremic toxins remains unconfirmed.
This knowledge-base record is being expanded from WikiBiome’s evidence graph.
Probiotic supplementation targeting the dysbiosis-thyroid axis aims to restore Lactobacillus and Bifidobacterium populations depleted in Hashimoto's thyroiditis, with potential downstream effects on iodine and selenium metabolism.
Probiotic supplementation targeting depleted Bifidobacterium and Lactobacillus in the postpartum period aims to restore gut-brain axis signaling disrupted during the dramatic hormonal shifts following delivery.
Co-administration of multi-strain probiotics (Bifidobacterium, Lactobacillus, Enterococcus, Bacillus cereus) alongside PPI therapy to mitigate PPI-induced gut dysbiosis. This addresses the treatment paradox: PPIs improve esophageal inflammation but worsen gut microbial …
Quinolinic acid (QA) is a neurotoxic metabolite of the kynurenine pathway — the branch of tryptophan catabolism driven by IFN-γ-induced IDO activation. QA is an NMDA receptor agonist that causes excitotoxic neuronal death at elevated concentrations. It is produced prima…
Saccharolytic fermentation is the microbial breakdown of carbohydrates (dietary fiber, resistant starch, host glycans) to produce short chain fatty acids (acetate, propionate, butyrate) and gases (H₂, CO₂, CH₄). It is the beneficial fermentation mode — the metabolic act…
Harm potential: YELLOW — True iron deficiency anemia requires supplementation regardless of inflammatory state.
Harm potential: GREEN — PPIs remain appropriate first-line therapy; this STOP recommends co-administration of probiotics, not PPI avoidance.
A synbiotic is a combination of live microorganisms (probiotics) and substrates selectively utilized by host microorganisms (prebiotics) that confers a health benefit. The rationale is additive or synergistic: the prebiotic component (typically inulin, fructo-oligosacch…
Restricting dietary nickel has clear benefits for nickel-sensitive individuals: it resolves SNAS symptoms, improves Ni ACM, and even enhances H. pylori eradication. Campanale et al. (2014) found that adding a nickel-free diet to standard triple therapy increased H. pylo…
Probiotics protect the gut barrier from heavy metal toxicity. Zhai et al. (2016) demonstrated that L. plantarum CCFM8610 protected intestinal epithelial cells from cadmium through a four-part mechanism: metal sequestration in the gut lumen, alleviation of oxidative stre…
Tryptophan (Trp) is an essential amino acid that the human body cannot synthesize and must obtain from diet. It occupies a uniquely important position at the intersection of neuroscience, immunology, and microbial ecology because it is the sole precursor to serotonin, a…
Tryptophan (Trp) is an essential amino acid metabolized via three competing pathways: the kynurenine pathway, the serotonin pathway, and the microbial indole pathway. The balance among these pathways is profoundly influenced by the gut microbiome, inflammation, and meta…
Type 1 diabetes is an autoimmune disease in which immune-mediated destruction of insulin-producing beta cells in the pancreatic islets of Langerhans leads to lifelong insulin dependence. T1D is fundamentally distinct from type 2 diabetes, which is characterized by insul…
Type 2 diabetes (T2D) is a metabolic disease characterized by insulin resistance and progressive beta-cell dysfunction, affecting over 500 million people worldwide (IDF Diabetes Atlas 2021). The conventional framing centers on caloric excess and sedentary behavior. The …
Vancomycin is a glycopeptide antibiotic targeting Gram-positive bacteria by binding D-Ala-D-Ala of peptidoglycan precursors. It is the last-resort treatment for MRSA and oral vancomycin is first-line for severe clostridioides difficile infection. In the WikiBiome framew…
Co-supplementation of vitamin D3 (50,000 IU every 2 weeks) + 4-strain probiotic (L. acidophilus, B. bifidum, L. reuteri, L. fermentum; 8 x 10^9 CFU/day) for 12 weeks, adjunctive to antipsychotics. This is the strongest single-trial result for a microbiome-targeted inter…