WikiBiomeThe human microbiome encyclopediaRanked matches across titles, topics, categories, and article introductions.
NiFe-hydrogenase (also called [Ni-Fe] hydrogenase or nickel-iron hydrogenase) is a class of enzymes that catalyze reversible hydrogen (H₂) oxidation. The active site contains both nickel (Ni) and iron (Fe) metal atoms arranged in a sophisticated bimetallic cluster. The …
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…
A chronic, relapsing-remitting inflammatory bowel disease (IBD) characterized by transmural inflammation of the gastrointestinal tract, most commonly affecting the terminal ileum and colon but capable of involving any segment from mouth to anus zhang 2017 intestinal mic…
Dermatitis herpetiformis (DH) is the cutaneous manifestation of celiac disease, presenting as intensely pruritic, grouped vesicles on the elbows, knees, buttocks, and scalp. It is driven by IgA antibodies against epidermal transglutaminase (eTG), the skin homolog of tis…
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…
A Gram-negative bacterium that spans the commensal-pathogen spectrum, with pathogenic variants (UPEC, STEC, EHEC) deploying nickel-dependent enzymes as virulence factors. E. coli is the model organism for nickel transport biology -- the NikABCDE system was first charact…
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…
A gastric pathogen that is arguably the most nickel-dependent human pathogen known. Two of its key virulence factors — urease and [NiFe] hydrogenase — require nickel, and the bacterium has evolved an elaborate nickel trafficking, storage, and regulation system to suppor…
[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…
Hyperandrogenism -- the clinical or biochemical excess of androgens (testosterone, androstenedione, DHEA-S) -- is a defining feature of polycystic ovary syndrome (PCOS), affecting 60-80% of women with the condition. It manifests as hirsutism, acne, androgenic alopecia, …
An umbrella term for chronic relapsing-remitting inflammatory conditions of the gastrointestinal tract, principally crohns disease (CD; transmural, any GI segment) and ulcerative colitis (UC; mucosal, colon only). Approximately 6 million patients worldwide. IBD represen…
Transition metals serve as essential cofactors for pathogen virulence factors across virtually all domains of microbial life. The dependence of pathogens on metals they must scavenge from the host environment creates a fundamental tension at the heart of infectious dise…
Methanobrevibacter smithii is the dominant methanogenic archaeon in the human gut, responsible for consuming hydrogen gas produced by fermentative bacteria and converting it to methane. Despite being an archaeon rather than a bacterium, it represents 0–15% of gut microb…
The causative agent of tuberculosis (TB), the leading infectious disease killer worldwide (~1.3 million deaths annually). M. tuberculosis has an exceptionally complex metal biology: it deploys nickel-dependent hydrogenase and urease for intracellular survival, species-s…
Specialized membrane proteins that import nickel into bacterial cells, supplying the essential cofactor for virulence enzymes including urease, NiFe hydrogenase, and Ni-glyoxalase. Because mammals produce no known nickel-requiring proteins, these transporters represent …
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…
A Gram-negative enteric pathogen that possesses four distinct hydrogenases of the [NiFe] class -- the most of any well-characterized human pathogen. These hydrogenases are critical for intracellular survival within macrophages, and a triple hydrogenase mutant is 100% av…
A Gram-negative intracellular pathogen causing bacillary dysentery (shigellosis), responsible for approximately 165 million illness episodes and over 1 million deaths annually, predominantly in children under 5 in developing countries. S. flexneri relies on nickel-depen…