28-Mer Fragment Derived From Enterocin CRL35 Displays an Unexpected Bactericidal Effect on Listeria Cells

EMILSE MASIAS; PAULO RICARDO DA SILVA SANCHES; LEONARDO ACUÑA; ROBERTO MORERO; AUGUSTO BELLOMIO; EDUARDO CILLI; LUCILA SAAVEDRA; CARLOS MINAHK

PROTEIN AND PEPTIDE LETTERS

BENTHAM SCIENCE PUBL LTD

Lugar: Oak Park; Año: 2015

0929-8665

Two shorter peptides derived from enterocin CRL35, a 43-mer bacteriocin, were synthesized i.e. a peptide fragment spanning from 1-15 enterocin CRL35 and a 28-mer fragment that represents 16-43 of this bacteriocin. Even though there was no reconstitution of the activity when both peptides were combined, the 28-mer peptide displayed an unpredicted antimicrobial activity. On the other hand, 15-mer peptide had no consistent antilisterial effect. The dissociation constants calculated from experimental data indicated that all peptides could bind at similar extent to the sensitive cells. However, they did not dissipate the transmembrane electrical potential to the same level. In fact, 15-mer fragment produced only a slow and incomplete dissipation. Furthermore, a different interaction of each peptide with membranes was demonstrated based on studies carried out with liposomes, which led us to conclude that activity was related to structure rather than to net positive charges. These results open up the possibility of designing new peptides based on the 28-mer fragment with enhanced activity, which would represent a promising approach for combating Listeria and other pathogens