Purity >95%. Indolicidin is a 13-residue peptide amide which was isolated and characterized from the cytoplasmic granules of bovine neutrophils;having potent antibacterial activity in vitro against bacteria and fungi. The primary structure of indolicidin is characterized by 5 tryptophan residues;which is the highest mole percentage of any known protein sequence and is unique among known endogenous antibacterial peptides.