Bacteriocin enterocin CRL35 is a modular peptide that induces non-bilayer states in bacterial model membranes

CAROLINA MEDINA AMADO; CARLOS J. MINAHK ; EDUARDO CILLI ; RAFAEL GUSTAVO OLIVEIRA; DUPUY FERNANDO G

BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019

0005-2736

he mechanism of action of the anti-Listeria peptide enterocin CRL35 was studied with biophysical tools by using lipid mixtures that mimicked Gram-positive plasma membranes. Langmuir monolayers and infrared spectroscopy indicated that the peptide readily interacted with phospholipid assembled in monolayers and bilayers to produce a dual effect, depending on the acyl chains. Indeed, short chain-fluid mixtures were disordered by enterocin CRL35, but the gel-phases of membranes composed by longer acyl chains were clearly stabilized by the bacteriocin. Structural and functional studies indicated that non-bilayer states were formed when liposomes were co-incubated with enterocin CRL35, whereas significant permeabilization could be detected when bilayer and non-bilayer states co-existed. Results can be explained by a two-step model in which the N-terminal of the peptide firstly docks enterocin CRL35 on the lipid surface by means of electrostatic interactions; then, C-terminal triggers membra