title: Surface-conjugated antimicrobial peptide leucocin a displays high binding to pathogenic gram-positive bacteria.
abstract: Leucocin A, a representative class IIa bacteriocin, is a ribosomally synthesized antimicrobial peptide (AMP) that displays potent activity against specific gram-positive bacteria. The antibacterial activity of such peptides is preceded by the binding event that can be utilized for studying specific peptide-bacteria interactions. In this study, 37-residue Leucocin A (LeuA) was synthesized using solid-phase peptide synthesis and covalently immobilized on gold substrates from either the N- or C-terminal. Both the peptide monolayers on gold substrates were incubated separately with five strains of gram-positive bacteria and displayed differential binding to different strains with highest binding to pathogenic Listeria monocytogenes . The C-terminally immobilized LeuA showed higher bacterial binding compared to the N-terminally attached LeuA. The full length immobilized LeuA (37-residue) was active as well as displayed higher bacterial binding (73 ± 6 bacteria/100 μm(2)) compared to 24-residue inactive LeuA fragment (40 ± 8 bacteria/100 μm(2)) from the C-terminal region. The high and specific bacterial binding ability of LeuA functionalized surfaces support the potential use of class IIa bacteriocins in antimicrobial peptide-based diagnostic platforms.
authors.affiliation: Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta , Edmonton, Alberta T6G 2E1, Canada.
authors.forename: Hashem
authors.initials: H
authors.lastname: Etayash
authors.forename: Lana
authors.initials: L
authors.lastname: Norman
authors.forename: Thomas
authors.initials: T
authors.lastname: Thundat
authors.forename: Michael
authors.initials: M
authors.lastname: Stiles
authors.forename: Kamaljit
authors.initials: K
authors.lastname: Kaur
mesh_terms: D000595:Amino Acid Sequence; D000890:Anti-Infective Agents / Q000737:chemistry* / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000737:chemistry* / Q000494:pharmacology; D001430:Bacteriocins / Q000737:chemistry* / Q000494:pharmacology; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006801:Humans; D008089:Listeria monocytogenes / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D013329:Structure-Activity Relationship
chemical_list: D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D001430:Bacteriocins; C071726:leucocin A-UAL 187