WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions.
Enterohepatic circulation (EHC) is the recycling loop by which compounds—primarily bile acids, conjugated estrogens, conjugated glucuronides, and metabolites of drugs and xenobiotics—are excreted in bile, reach the intestine, undergo deconjugation or dehydroxylation by …
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…
Hepatitis (liver inflammation) encompasses viral (HBV, HCV, HAV), autoimmune, alcoholic, and toxin-induced forms. In the WikiBiome framework, the gut-liver axis is central — portal blood delivers gut-derived microbial products (LPS, bacterial DNA) directly to the liver …
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…
Antimicrobial metals are metal ions and metal-based materials that kill or inhibit microorganisms. Copper, silver, zinc, and gallium are the principal agents, each exploiting different aspects of microbial metal biology. What makes this field particularly relevant to Wi…
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…
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…
Bile acids are cholesterol-derived amphipathic molecules synthesized in the liver, secreted into the duodenum, and extensively modified by gut bacteria. The host-microbe co-metabolism of bile acids creates a signaling network with profound effects on lipid metabolism, g…
Breast cancer is the most common cancer in women worldwide, with approximately 2.3 million new cases annually. While genetic, hormonal, and lifestyle factors are well-established risk determinants, the metallomic dimension reveals a consistent pattern of trace element d…
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…
Cholestasis is the impairment or cessation of bile flow from the liver to the duodenum. It can be intrahepatic (hepatocyte or bile ductule dysfunction) or extrahepatic (mechanical obstruction). Beyond its direct hepatic consequences, cholestasis profoundly disrupts the …
Chromium is a transition metal (atomic number 24) whose toxicology is defined by a stark oxidation-state divide. Hexavalent chromium, Cr(VI), is an IARC Group 1 human carcinogen that causes DNA damage through a unique mechanism of intracellular reduction and ternary add…
Cirrhosis is end-stage liver fibrosis characterized by nodular regeneration, portal hypertension, and progressive hepatic failure. The gut-liver axis is central: portal venous blood delivers gut-derived LPS, bacterial DNA, and viable bacteria directly to the liver, and …
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…
Deinococcus is a genus of extremophilic bacteria famous for extraordinary resistance to ionizing radiation, desiccation, and oxidative stress. D. radiodurans — "Conan the Bacterium" — can survive radiation doses 1,000 times greater than those lethal to humans. This resi…
arsenic (As) is unique among dietary heavy metals because it exists in two fundamentally different forms with dramatically different toxicities: inorganic arsenic (iAs, the dangerous form) and organic arsenic (arsenobetaine, arsenosugars — largely non-toxic). Understand…
Direct DNA damage is the primary carcinogenic mechanism for chromium but is notably absent or minor for nickel and arsenic. This distinction is fundamental to understanding why these three metals cause cancer through such different pathways.
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, …
Escherichia is a genus of Gram-negative, facultatively anaerobic bacteria in the Enterobacteriaceae family. The primary species E. coli is simultaneously the most studied bacterium in biology and one of the most consistently enriched organisms in disease-associated micr…
The estrobolome is the aggregate of enteric bacterial genes whose products are capable of metabolizing estrogens. First proposed by Plottel and Blaser (2011), the concept describes how the gut microbiome acts as an endocrine organ, modulating circulating estrogen levels…
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…
Eubacteriales Buchanan 1917 (Approved Lists 1980) is the current correct name for NCBITaxon:186802. LPSN records Clostridiales Prévot 1953 (Approved Lists 1980) as a validly published heterotypic synonym, not a separate current order ncbi taxonomy eubacteriales lpsn eub…
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.
The only known cellular iron exporter in mammals. Encoded by the SLC40A1 gene, ferroportin (FPN) sits on the basolateral membrane of enterocytes, the surface of macrophages, and the membrane of hepatocytes, controlling the flow of iron from these cells into the bloodstr…
Ferroptosis is a form of iron-dependent regulated cell death driven by the accumulation of lipid peroxides on cellular membranes pendergrass 2026 microbial metallomics parkinsons ferroptosis, riederer 2021 iron concert master parkinsons. Unlike apoptosis or necrosis, fe…
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…
The gut-thyroid axis describes the bidirectional communication between the gut microbiome and the thyroid gland. The thyroid regulates metabolism, energy homeostasis, and immune function -- and the microbiome influences thyroid physiology at every level: mineral absorpt…
The master regulator of systemic iron homeostasis. Hepcidin is a 25-amino-acid peptide hormone produced primarily by hepatocytes that controls iron absorption, recycling, and distribution by binding to and degrading ferroportin (SLC40A1/FPN) -- the only known cellular i…
[NiFe] hydrogenases are the second major nickel-dependent virulence factor class in human pathogens. Less widespread than urease but critical for energy metabolism in gastric, enteric, and intracellular pathogens. The discovery that H. pylori hydrogenase powers CagA tra…
Indoxyl sulfate (IS) is a protein-bound uremic toxin produced through a two-step process: gut bacteria convert dietary tryptophan to indole, which is then absorbed and sulfated by hepatic sulfotransferases (SULT1A1). IS exemplifies how dysbiosis-driven metabolite overpr…
Innate immunity is the body's first-line, non-specific defense against pathogens — comprising physical barriers (epithelium, mucus), antimicrobial molecules (calprotectin, lactoferrin, defensins), pattern recognition receptors (TLRs, NOD-like receptors), and phagocytic …
Interleukin-22 (IL-22) is an immune signaling protein that helps coordinate host responses at epithelial surfaces. In the gut evidence represented by WikiBiome, group 3 innate lymphoid cells (ILC3s) are a prominent source, while Th17-associated responses can also includ…
The intestinal epithelium is a single-cell-thick barrier separating the lumen -- home to trillions of microbes and ingested metals -- from the systemic circulation. When this barrier fails, the consequences cascade: microbial products translocate, metals gain unrestrict…
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…
Ketone bodies (beta-hydroxybutyrate [BHB], acetoacetate, acetone) are produced by hepatic fatty acid oxidation during carbohydrate restriction, fasting, or ketogenic diet consumption. BHB is the most abundant and is structurally and functionally analogous to butyrate — …
Lipid metabolism — the synthesis, transport, and degradation of fats — is profoundly modulated by both the gut microbiome and metal homeostasis. The microbiome influences lipid metabolism through bile acid transformation, SCFA production, TMAO generation, and direct enz…
Post-acute sequelae of SARS-CoV-2 infection (PASC), affecting an estimated 10-30% of COVID-19 survivors (WHO and CDC post-acute surveillance estimates) with symptoms persisting 12 weeks. Characterized by fatigue, cognitive dysfunction ("brain fog"), exercise intolerance…
The ability of certain metals to cause cancer has been known since the 19th century. The three metals covered in this wiki — nickel, arsenic, and chromium — represent distinct mechanistic paradigms that collectively illustrate the diversity of metal-induced carcinogenes…
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…
A transition metal occupying a central position in this wiki's evidence base. Nickel is toxic and carcinogenic to humans, yet an essential cofactor for pathogen virulence enzymes. It is the most frequent contact allergen worldwide and drives a wide spectrum of systemic …
Non-alcoholic fatty liver disease (NAFLD), recently reclassified as metabolic dysfunction-associated steatotic liver disease (MASLD), encompasses a spectrum from simple hepatic steatosis to metabolic dysfunction-associated steatohepatitis (MASH, formerly NASH), fibrosis…
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…
Postbiotics are defined by ISAPP (2021) as "preparations of inanimate microorganisms and/or their components that confer a health benefit on the host." They include heat-killed bacteria, cell-free supernatants, bacterial lysates, and purified microbial metabolites (SCFA…
Shotgun metagenomics is a sequencing approach that fragments and sequences all DNA in a sample -- bacterial, archaeal, fungal, viral, and host -- without prior amplification of a specific gene target. Unlike 16S rRNA amplicon sequencing, which identifies "who is there" …
Vitamin C (ascorbate) is broadly protective: it reduces nickel absorption from food (acting as a competitive inhibitor in the GI tract), is the most commonly recommended adjunct to low-nickel diets zirwas 2009 dietary nickel dermatitis, and is a critical cofactor for DN…
Copper is elevated in the blood/serum of nearly every disease state examined in this wiki: | Disease | Cu Direction | Evidence | |---|---|---| | PCOS | Elevated | SMD = 0.51, p < 0.0001 (meta-analysis of 9 studies) | | Breast cancer | Elevated | SMD 2.44 in plasma/serum…
Fish is the primary dietary source of methylmercury (MeHg) -- a potent neurotoxin that crosses the blood-brain barrier, depletes glutathione, and can increase amyloid-beta production and tau phosphorylation mercury. MeHg is 95-100% absorbed in the intestinal tract. An e…
Tight junctions are the multiprotein complexes that seal the paracellular space between intestinal epithelial cells, forming the physical barrier that separates the gut lumen (with its ~10^13 bacteria, LPS, and dietary antigens) from the underlying lamina propria and sy…
A gut microbiome-derived metabolite that has emerged as one of the strongest microbial biomarkers for cardiovascular disease risk. TMAO exemplifies how microbial metabolism of dietary nutrients can generate systemically toxic products -- a fundamentally different paradi…
Urea is the substrate of urease. In the microbial systems covered by WikiBiome, urease hydrolyzes urea to ammonia and bicarbonate; those products can supply microbial nitrogen and help neutralize acidic environments maier 2019 nickel microbial pathogenesis. At a glance,…
Ursodeoxycholic acid is a hydrophilic secondary bile acid used therapeutically for primary biliary cholangitis (PBC), gallstone dissolution, and cholestatic liver disease. It is also a microbial metabolite — gut bacteria (7α/β-hydroxysteroid dehydrogenases) convert chen…