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

• Autor(a) principal: Medina Amado, Carolina
• Data de Publicação: 2020
• Outros Autores: Minahk, Carlos J., Cilli, Eduardo [UNESP], Oliveira, Rafael G., Dupuy, Fernando G.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.bbamem.2019.183135; http://hdl.handle.net/11449/201338
• topic: Bacterial membrane; Bacteriocin; Listeria; Monolayer; Spectroscopy; X-ray diffraction

The 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 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 membrane perturbation by insertion of hydrophobic α-helix.