Search of novel antimicrobial peptides of the cathelicidins and defensins families in moose (Alces alces) leucocytes

Abstract

Antimicrobial peptides (AMPs) of animal origin are cationic molecules that play an important role in the innate immune defense. An investigation of new AMPs is important for the development of fundamental knowledge on the molecular mechanisms of innate immunity in the course of evolution, as well as for the production of novel structures, which may serve as templates for the design of new antibiotic drugs. The purpose of the present work is to investigate physicochemical properties and biological activity of antimicrobial peptides from the moose (Alces alces) leukocytes. By using a preparative procedure containing an ultrafiltration and reverse-phase HPLC we have isolated and characterized five highly purified preparations of peptides (AP 2–6) with the molecular masses of 1849, 3696, 2418, 2003 and 2858 Da. The preparation AP-1 included a peptide with a molecular mass of 4658 Da, similar to that of bovine β-defencin. The peptide AP-5 possessed the highest electrophoretic mobility in the acidic environment toward a cathode. The peptides AP-2, AP-3, AP-4, AP-6 appeared to be linear molecules, while the peptides AP-1 and AP-5 contained S-S bridges. The obtained peptides showed antimicrobial activity against gram-negative bacteria Escherichia coli ML-35p and gram-positive bacteria Listeria monocytogenes EGD, but did not lyse human red blood cells in concentrations five times exceeded MIC values. Refs 23. Figs 5. Таbles 1.

Keywords:

innate immune system, antimicrobial peptides, cathelicidins