Ocellatin-PT Antimicrobial Peptides: High Resolution Microscopy Studies in Antileishmania Models and Interactions with Mimetic Membrane Systems

OLIVEIRA MAYARA; GOMES-ALVES ANA G.; SOUSA CARLA; MARANI MARIELA M.; PLACIDO ALEXANDRA; ´VALE NUNO; DELERUE-MATOS MARÍA C.; GAMEIRO PAULA; KUCKELHAUS SELMA A.S.; TOMAS ANA M.; LEITE JOSÉ R. S. A.; EATON PETER

BIOPOLYMERS

JOHN WILEY & SONS INC

Lugar: New York; Año: 2016 vol. 105 p. 873 - 886

0006-3525

The mechanisms of action of antimicrobial peptides (AMPs) on parasites are not fully understood. However, in many cases, AMPs kill target cells by disrupting the cell membrane, their effects being related to their affinities to membranes of varying lipid compositions. New ocellatin-PT peptides were recently isolated from the skin secretion of Leptodactylus pustulatus. In this paper we evaluate ocellatin-PT antiparasitic activity against Leishmania infantum. We characterized the peptide?s secondary structures and evaluated their affinity to different lipid systems using SPR. The results demonstrates that all ocellatins-PT have a solvent-dependent alpha helix structure adoption, five peptides present antiparasitic activity (IC50) lower than 15 µM and that PT-1 and PT-8 show considerable changes in the membranes of the parasite body and a higher affinity for leishmania and bacteria lipid membrane models rather than mammalian lipid membranes, demonstrating selectivity towards parasite model membranes for these AMPs.