Antimicrobial peptides (AMPs) play an important role in the innate defense mechanisms in humans and animals. We have isolated and studied a set of antimicrobial peptides from leukocytes of the Russian sturgeon Acipenser gueldenstaedtii belonging to a subclass of chondrosteans, an ancient group of bony fish. Structural analysis of the isolated peptides, designated as acipensins (Ac), revealed in leukocytes of the Russian sturgeon six novel peptides with molecular masses of 5336.2 Da, 3803.0 Da, 5173.0 Da, 4777.5 Da, 5449.4 Da, and 2740.2 Da, designated as Ac1-Ac6, respectively. Complete primary structures of all the isolated peptides were determined, and the biological activities of three major components Ac1, Ac2, and Ac6 were examined. The peptides Ac1, Ac2, Ac3, Ac4, and Ac5 were found to be the N-terminal acetylated fragments 1-50, 1-35, 1-49, 1-44, and 1-51 of the histone H2A, respectively, while Ac6 was shown to be the 62-85 fragment of the histone H2A. The peptides Ac1 and Ac2 displayed potent antimicrobial activity towards Gram-negative and Gram-positive bacteria (Escherichia coli ML35p, Listeria rnonocytogenes EGD, MRSA ATCC 33591) and the fungus Candida albicans 820, while Ac6 proved effective only against Gram-negative bacteria. The efficacy of Ac 1 and Ac2 towards the fungus and MRSA was reduced upon an increase in the ionic strength of the solution. Ad, Ac2, and Ac6, at concentrations close to their minimum inhibitory concentrations, enhanced the permeability of the E.co/i ML35p outer membrane to the chromogenic marker, but they did not affect appreciably the permeability of the bacterial inner membrane in comparison with a potent pore-forming peptide, protegrin 1. Ad, Ac2, and Ac6 revealed no hemolytic activity against human erythrocytes at concentrations of 1 to 40 mu M and had no cytotoxic effect (1 to 20 mu M) on K-562 and U-937 cells in vitro. Our findings suggest that histone-derived peptides serve as important anti-infective host defense molecules.

Original languageEnglish
Pages (from-to)99-109
Number of pages11
JournalActa Naturae (англоязычная версия
Volume6
Issue number4
StatePublished - 2014

    Research areas

  • innate immunity, antimicrobial peptides, sturgeon leukocytes, histone H2A derivatives, acipensin, POLYACRYLAMIDE-GEL ELECTROPHORESIS, SALMON SALMO-SALAR, HISTONE H1, ONCORHYNCHUS-MYKISS, CATHELICIDIN GENE, WINTER FLOUNDER, RAINBOW-TROUT, BETA-DEFENSIN, PARASIN-I, PROTEINS

ID: 7034083