Positively charged gramicidin A based peptides form two types of membrane channels
In recent years investigation of new membrane-active antimicrobial peptides attracted much attention. At present at least 5 types of pore structures are proposed: rigid intramolecular tubes formed by head-to-head dimerization of gramicidin A (gA) , intramolecular pores resulting from stacking of cyclic peptides , intermolecular “barrel-stave” pores formed by bundles of α-helical rods of alamethicin , porin-like high-conductance intermolecular pores with a β-barrel structure , intermolecular peptide—lipidic pores with pore walls formed both by peptide molecules and lipid headgroups [5, 6].
The factors remain unclear for forming pores of different structure by peptide molecules of one sort. Searching of new pore structure types also is of great interest. In the present work, we addressed this question by studying the activity of gramicidin A positively charged derivatives. It was found that peptides having a positively charged moiety conjugated with gramicidin A...
KeywordsCyclic Peptide Bilayer Lipid Membrane Choline Chloride Peptide Molecule Lipid Headgroups
This work was supported in part by a grant from the RFBR: 06-04-48523 (Y.N.A.).