Selective reciprocity in antimicrobial activity versus cytotoxicity of hBD-2 and crotamine.

ABSTRACT: Recent discoveries suggest cysteine-stabilized toxins and antimicrobial peptides have structure-activity parallels derived by common ancestry. Here, human antimicrobial peptide hBD-2 and rattlesnake venom-toxin crotamine were compared in phylogeny, 3D structure, target cell specificity, and mechanisms of action. Results indicate a striking degree of structural and phylogenetic congruence. Importantly, these polypeptides also exhibited functional reciprocity: (i) they exerted highly similar antimicrobial pH optima and spectra; (ii) both altered membrane potential consistent with ion channel-perturbing activities; and (iii) both peptides induced phosphatidylserine accessibility in eukaryotic cells. However, the Na(v) channel-inhibitor tetrodotoxin antagonized hBD-2 mechanisms, but not those

SUBMITTER: Yount NY 

PROVIDER: S-EPMC2736466 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature