Antimicrobial Peptides (AMPs)
Plain-English definitions of microbiome research vocabulary — the terms you'll see across articles, testing services, and probiotic claims.
Small proteins produced by both the host (intestinal epithelial cells) and commensal bacteria that kill or inhibit pathogenic microorganisms. AMPs are a critical component of innate immunity in the gut and on the skin. Defensins, cathelicidins, and bacteriocins are common examples.
Related terms
Colonisation Resistance
The ability of the resident microbiome to prevent colonisation by pathogenic organisms. A diverse, healthy microbiome provides strong colonisation resistance through competition for nutrients and space, and production of antimicrobial compounds.
Commensal
An organism that benefits from a relationship with another organism without causing harm. Most gut bacteria are commensals — they gain food and shelter while contributing to digestion, immunity, and barrier function.