Elaboration of antibiofilm materials by chemical grafting of an antimicrobial peptide.
A peptide antibiotic, gramicidin A, was covalently bound to cystamine self-assembled monolayers on gold surfaces. Each step of the surface functionalization was characterized by polarization modulation infrared reflection absorption spectroscopy and X-ray photoelectron spectroscopy. The antimicrobial activity of the anchored gramicidin was tested against three Gram-positive bacteria (Listeria ivanovii, Enterococcus faecalis, and Staphylococcus aureus), the Gram-negative bacterium Escherichia coli and the yeast Candida albicans. The results revealed that the adsorbed gramicidin reduced, from 60% for E. coli to 90% for C. albicans, the number of culturable microorganisms attached to the surface. The activity was proven to be persistent overtime, up to 6 months after the first use. The bacteria attached to the functionalized surfaces were permeabilized as shown by confocal microscopy. Taken together, these results indicate a bacteriostatic mode of action of the immobilized peptide. Finally, using green fluorescent protein-expressing bacteria, it was shown that the development of a bacterial biofilm was delayed on peptide-grafted surfaces for at least 24 h.
Yala
Jean-Fabrice
JF
CNRS, IBMIG-UFR Sciences fondamentales et Appliquées, Université de Poitiers, France.
Thebault
Pascal
P
Héquet
Arnaud
A
Humblot
Vincent
V
Pradier
Claire-Marie
CM
Berjeaud
Jean-Marc
JM
D023181:Antimicrobial Cationic Peptides / Q000378:metabolism*; D018441:Biofilms / Q000187:drug effects*; D002176:Candida albicans / Q000187:drug effects*; D004926:Escherichia coli / Q000187:drug effects*; D006046:Gold; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006096:Gramicidin / Q000378:metabolism*; D050296:Microbial Viability / Q000187:drug effects; D013499:Surface Properties
D023181:Antimicrobial Cationic Peptides; D006096:Gramicidin; D006046:Gold