Host-defense peptide that maintains sterility in the urogenital system (By similarity). Has antimicrobial activity against a wide range of bacteria, including Gram-negative E.coli, P.aeruginosa and S.typhimurium, and Gram-positive E.aerogenes, S.aureus, B.cereus, E.faecium and L.monocytogenes (By similarity). Confers resistance to intestinal infection by S.typhimurium (By similarity). Exhibits antimicrobial activity against enteric commensal bacteria such as B.adolescentis, L.acidophilus, B.breve, L.fermentum, B.longum and S.thermophilus (By similarity). Binds to bacterial membranes and causes membrane disintegration (By similarity). Induces the secretion of the chemokine IL-8 by intestinal epithelial cells (By similarity). Binds to B.antracis lef/lethal factor, a major virulence factor from B.anthracis, and neutralizes its enzymatic activity (By similarity).
Subcellular locations: Secreted, Cytoplasmic vesicle, Secretory vesicle
Stored as propeptide HD5(20-94) in secretory granules of small intestinal Paneth cells and found in the ileum lumen as processed mature peptides, predominantly in the HD5(63-94) form. Peptides HD5(20-94), HD5(23-94) and HD5(29-94) are found within tissues, HD5(20-94) being the predominant intracellular form. Peptides HD5(56-94) and HD5(63-94) are found in the extracellular milieu, HD5(63-94) being the most abundant form (By similarity). Secreted into the female genital tract lumen (By similarity).