SMAP-29: a potent antibacterial and antifungal peptide from sheep leukocytes

SMAP-29 is a cathelicidin-derived peptide deduced from sheep myeloid mRNA, The C-terminally amidated form of this peptide was chemically synthesized a nd shown to exert a potent antimicrobial activity. Antibiotic-resistant cli nical isolates highly susceptible to this peptide include MRSA and VREF iso lates, that are a major worldwide problem, and mucoid Pseudomonas aeruginos a associated with chronic respiratory inflammation in CF patients. In addit ion, SMAP-29 is also active against fungi, including Cryptococcus neoforman s isolated from immunocompromised patients. SMAP-29 causes significant morp hological alterations of the bacterial surfaces, as shown by scanning elect ron microscopy, and is also hemolytic against human, but not sheep erythroc ytes. Its potent antimicrobial activity suggests that this peptide is an ex cellent candidate as a lead compound for the development of novel antiinfec tive agents. (C) 1999 Federation of European Biochemical Societies.