Tyrocidine is a family of eight cationic cyclic decapeptides produced by Bacillus brevis, first reported by Dubos in 1941. Tyrocidines exhibit broad antibiotic activity against Gram positive and negative bacteria and are the major component of the tyrothricin complex which is used for treatment of topical infections. Although the mechanism of action of tyrocidines is not fully understood, they are known to act by disturbing lipid bilayers of the bacterial cell membrane.
