Abstract: Artificial antimicrobial peptides are obtained by alterations in alpha helical portions of a known antimicrobial protein, granulysin. The peptides obtained have significantly improved antimicrobial activity and lack the ability to lyse mammalian cells, which may be toxic to a host. The peptides may be designed according to certain guidelines, and may further be modified by the addition of altered residues and alterations in normal peptide secondary and tertiary structure, including modifications in quaternary (multimeric) structure.