Negative Dipole Potentials and Carboxylic Polar Head Groups Foster the Insertion of Cell-Penetrating Peptides into Lipid Monolayers

VIA, MATÍAS A.; DEL PÓPOLO, MARIO G.; WILKE, NATALIA

LANGMUIR

AMER CHEMICAL SOC

Año: 2018 vol. 34 p. 3102 - 3102

0743-7463

ell-penetrating peptides (CPPs) are polycationic sequences ofamino acids recognized as some of the most effective vehicles for deliveringmembrane-impermeable cargos into cells. CPPs can traverse cell membranes bydirect translocation, and assessing the role of lipids on the membrane permeationprocess is important to convene a complete model of the CPP translocation. In thiswork, we focus on the biophysical basis of peptide−fatty acid interactions, analyzinghow the acid−base and electrostatic properties of the lipids determine the CPPadsorption and incorporation into a Langmuir monolayer, focusing thus on the firsttwo stages of the direct translocation mechanism. We sense the binding andinsertion of the peptide into the lipid structure by measuring the changes in thesurface pressure, the surface potential, and the reflectivity of the interface. We showthat, beyond the presence of anionic moieties, negative dipole potentials and carboxylic polar head groups significantly prom