WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions, filtered to mechanism.
Iron-sulfur (Fe-S) clusters are among the most ancient and ubiquitous metal cofactors in biology, present in all domains of life. These inorganic prosthetic groups -- typically [2Fe-2S] or [4Fe-4S] configurations -- mediate electron transfer, enzymatic catalysis, and re…
Catalase is a heme-iron enzyme that decomposes hydrogen peroxide into water and oxygen. In microbial peroxide defense, it acts downstream of superoxide dismutase: superoxide dismutase converts superoxide to hydrogen peroxide, and catalase removes that hydrogen peroxide …
A distinct form of regulated cell death caused by excess intracellular copper binding to lipoylated proteins in the TCA cycle, first characterized by Tsvetkov et al. in Science (2022). Unlike ferroptosis (iron-dependent lipid peroxidation) or apoptosis (caspase-dependen…
Disruption of the normal composition and metabolic function of microbial communities, particularly the gut microbiome. In the metallomics context, dysbiosis is both a consequence of metal toxicity and an amplifier of further disease -- creating vicious cycles where meta…
Gene regulation in bacteria is the process by which cells control when and how much of each gene product is made. In the metallomics context, gene regulation is the mechanism by which bacteria respond to the metal environment -- sensing metal availability and adjusting …
The gut-testis axis describes the bidirectional communication between the gut microbiome and the male reproductive system. Gut-derived microbial metabolites, immune signals, and systemic inflammatory mediators influence testicular function, testosterone biosynthesis, an…
Homocysteine is a sulfur-containing amino acid intermediate in the methionine cycle. Elevated plasma homocysteine (hyperhomocysteinemia) is an established risk factor for cardiovascular disease, endothelial dysfunction, and neurodegenerative disease. The gut microbiome …
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…
Metal sensing is the set of regulatory mechanisms bacteria use to detect intracellular metal concentrations and adjust gene expression accordingly. Because metal ions cannot be synthesized or degraded -- only imported, exported, sequestered, or trafficked -- sensing and…
Protein-based transcription factors that sense intracellular metal concentrations and regulate gene expression accordingly. Metalloregulators are the decision-making layer of bacterial metal homeostasis -- they read the labile metal pool, determine whether a specific me…
Mis-metallation is the displacement of the correct metal cofactor from an enzyme or protein by a wrong metal ion, leading to loss of function, gain of aberrant function, or structural disruption. This is one of the most fundamental and pervasive mechanisms of metal toxi…
Mitochondrial dysfunction refers to the impairment of mitochondrial energy production, redox balance, and signaling functions. Mitochondria are the primary targets of heavy metal toxicity in human cells, and they are also the organelles most dependent on metal cofactors…
Small regulatory RNAs (sRNAs) are non-coding RNA molecules, typically 50-500 nucleotides long, that regulate gene expression post-transcriptionally in bacteria. In the context of metal biology and microbial pathogenesis, sRNAs serve as rapid-response coordinators that h…
Taurine (2-aminoethanesulfonic acid) is a sulfur-containing amino acid abundant in bile, heart, brain, and retina. Its primary metabolic role is bile acid conjugation — taurocholate and taurochenodeoxycholate are the taurine-conjugated primary bile acids that BSH-produc…