Elastic behavior of model membranes with antimicrobial peptides depends on lipid specificity and d-enantiomers.

Autor: Kumagai A; Biological Physics Group, Physics Department, Carnegie Mellon University, Pittsburgh, PA, USA. stn@cmu.edu., Dupuy FG, Arsov Z, Elhady Y, Moody D, Ernst RK, Deslouches B, Montelaro RC, Peter Di Y, Tristram-Nagle S
Jazyk: angličtina
Zdroj: Soft matter [Soft Matter] 2019 Feb 20; Vol. 15 (8), pp. 1860-1868.
DOI: 10.1039/c8sm02180e
Abstrakt: In an effort to provide new treatments for the global crisis of bacterial resistance to current antibiotics, we have used a rational approach to design several new antimicrobial peptides (AMPs). The present study focuses on 24-mer WLBU2 and its derivative, D8, with the amino acid sequence, RRWVRRVRRWVRRVVRVVRRWVRR. In D8, all of the valines are the d-enantiomer. We use X-ray low- and wide-angle diffuse scattering data to measure elasticity and lipid chain order. We show a good correlation between in vitro bacterial killing efficiency and both bending and chain order behavior in bacterial lipid membrane mimics; our results suggest that AMP-triggered domain formation could be the mechanism of bacterial killing in both Gram-positive and Gram-negative bacteria. In red blood cell lipid mimics, D8 stiffens and orders the membrane, while WLBU2 softens and disorders it, which correlate with D8's harmless vs. WLBU2's toxic behavior in hemolysis tests. These results suggest that elasticity and chain order behavior can be used to predict mechanisms of bactericidal action and toxicity of new AMPs.
Databáze: MEDLINE