bacitracin

Bacitracin A is a homodetic cyclic peptide consisting of (4R)-2-[(1S,2S)-1-amino-2-methylbutyl]-4,5-dihydro-1,3-thiazole-4-carboxylic acid attached head-to-tail to L-leucyl,D-glutamyl, L-lysyl, D-ornityl, L-isoleucyl, D-phenylalanyl, L-histidyl. D-aspartyl and L-asparaginyl residues coupled in sequence and cyclised by condensation of the side-chain amino group of the L-lysyl residue with the C-terminal carboxylic acid group. It is the major component of bacitracin. It has a role as an antimicrobial agent and an antibacterial agent. It is a polypeptide and a homodetic cyclic peptide.