Granulysin: a novel antimicrobial

Granulysin is a novel lyric molecule produced by human cytolytic T-lymphocy tes (CTLs) and natural killer (NK) cells. It is active against a broad rang e of microbes, including Gram-positive and -negative bacteria, parasites an d Mycobacterium tuberculosis. It is functionally related to other antibacte rial peptides, like defensins and magainins, but is structurally distinct. It has structural similarity to porcine NK-lysin and to amoebapores made by Entamoeba histolytica. Synthetic peptides derived from granulysin have dif ferential activity against eukaryotic cells and bacteria. Selective bacteri cidal peptides may have therapeutic roles as novel antibiotics.