The defensin–lipid interaction: Insights on the binding states of the human antimicrobial peptide HNP-1 to model bacterial membranes

July 28, 2017

Title

The defensin–lipid interaction: Insights on the binding states of the human antimicrobial peptide HNP-1 to model bacterial membranes

Author

Alessio Bonucci, Enrico Balducci, Sara Pistolesi, Rebecca Pogni

Year

2013

Journal

Biochimica et Biophysica Acta (BBA) - Biomembranes

Abstract

Antimicrobial peptides are an important component of innate immunity and have generated considerable interest as a new potential class of natural antibiotics. The biological activity of antimicrobial peptides is strongly influenced by peptide–membrane interactions. Human Neutrophil Peptide 1 (HNP-1) is a 30 aminoacid peptide, belonging to the class of α-defensins. Many biophysical studies have been performed on this peptide to define its mechanism of action. Combining spectroscopic and thermodynamic analysis, insights on the interaction of the α-defensin with POPE:POPG:CL negative charged bilayers are given. The binding states of the peptide below and above the threshold concentration have been analyzed showing that the interaction with lipid bilayers is dependent by peptide concentration. These novel results that indicate how affinity and biological activities of natural antibiotics are depending by their concentration, might open new way of investigation of the antimicrobial mode of action.

Instrument

J-815

Keywords

Circular dichroism, Secondary structure, Aggregation, Vesicle interactions, Biochemistry