WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions.
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…
The ability of microorganisms to survive and replicate in the presence of antimicrobial agents — antibiotics, antifungals, antivirals, antiparasitic drugs — at concentrations that would normally inhibit or kill them. Antimicrobial resistance (AMR) is designated by the W…
Arsenic is a metalloid and potent carcinogen (IARC Group 1) that ranks among the most widespread environmental toxicants affecting human health. An estimated 225 million people worldwide are chronically exposed through contaminated drinking water alone ghosh 2023 heavy …
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 …
Caulobacter is a genus of Gram-negative obligate aerobic Alphaproteobacteria, with C. crescentus serving as one of the premier model organisms for studying bacterial cell biology. Found primarily in oligotrophic freshwater environments, Caulobacter is not a gut commensa…
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…
The process by which selection pressure from one agent — typically a heavy metal — simultaneously selects for resistance to a structurally unrelated agent such as an antibiotic, because the resistance determinants are genetically linked on the same mobile genetic elemen…
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…
lead (Pb) has no safe level of exposure. Unlike most dietary metals, lead does not play any known biological role — every atom absorbed represents toxic burden. While environmental lead exposure (paint, soil, air) has decreased dramatically since leaded gasoline phase-o…
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…
This page addresses the practical question: how do toxic metals get into people? Metal toxicology research identifies the mechanisms of harm, but understanding exposure routes -- dietary, occupational, environmental, and consumer product-mediated -- is essential for pre…
Flavobacterium is a genus of Gram-negative, aerobic bacteria within the phylum Bacteroidetes. Primarily environmental organisms found in soil and freshwater, Flavobacterium species have been identified in human microbiome studies of the cervical and reproductive tract, …
Methylobacterium is a genus of methylotrophic alpha-Proteobacteria (phylum Pseudomonadota) predominantly found in soil, water, plant surfaces, and air environments. It is a methylotroph — capable of using one-carbon compounds such as methanol as a carbon and energy sour…
Sphingomonas is a genus of Gram-negative, aerobic, rod-shaped bacteria in the class Alphaproteobacteria, distinguished by the presence of sphingolipids in their outer membrane rather than the lipopolysaccharide (LPS) typical of most Gram-negative bacteria. Originally is…
The exposome is the totality of environmental exposures an individual experiences from conception to death. Coined by Christopher Wild in 2005, it complements the genome by capturing the environmental side of the gene-environment equation. Metals are among the most quan…
Trichosporon asahii is a basidiomycetous yeast found in soil, water, and on human skin. It is the primary cause of invasive trichosporonosis in immunocompromised patients, particularly those with neutropenia or hematologic malignancies. It is inherently resistant to ech…