SMAP-18 is a biological active peptide. (SMAP-18 is a 18-amino acid residue peptide amide which is a truncated form of SMAP-29. Sheep myeloid antimicrobial peptide-29 (SMAP-29) displays extremely high antimicrobial activity against Pseudomonas strains, other Gram-negative bacteria, and multidrug-resistant pathogens. SMAP-18 displays much higher cell selectivity as compared to parental SMAP-29 because of its decreased hemolytic activity and retained antimicrobial activity.)