The insertion of Polybia-MP1 peptide into phospholipid monolayers is regulated by its anionic nature and phase state

ALVARES, DAYANE S.; WILKE, NATALIA; RUGGIERO NETO, JOÃO; FANANI, MARIA LAURA

CHEMISTRY AND PHYSICS OF LIPIDS

ELSEVIER IRELAND LTD

Año: 2017 vol. 207 p. 38 - 38

0009-3084

olybia-MP1 or simply MP1 (IDWKKLLDAAKQIL-NH2) is a peptide with broad-spectrum bactericidal activity and a strong inhibitory effect against cancer cells. The aim of this work was to evaluate the effect of biophysical properties such as membrane texture and film thickness on MP1 interaction with neutral and anionic lipid membranes. For this purpose, we first explored the peptide´s surface behavior. MP1 showed high surface activity, adsorbing onto bare air/aqueous interfaces up to higher surface pressures than the collapse pressure of MP1 Langmuir films. The MP1-lipid membrane interaction was studied using Langmuir phosphatidylcholine and phosphatidylserine (PS) monolayers as model membrane systems. PS was chosen since this negatively charged lipid was found predominantly on the outer leaflet of tumor cells, and it enhances MP1 activity for PS-containing membranes to a greater extent than for other negatively charged lipids. MP1 incorporated into anionic PS monolayers, which show a liqu