Avtor/Urednik     Morisset, Dany; Berjeaud, Jean-Marc; Marion, Didier; Lacombe, Christian; Frere, Jacques
Naslov     Mutational analysis of mesentericin Y105, an anti-Listeria bacteriosin, for determination of impact on bactericidal activity, in vitro secondary structure, and membrane interaction
Tip     članek
Vir     Appl Environ Microbiol
Vol. in št.     Letnik 80, št. 8
Leto izdaje     2004
Obseg     str. 4672-70
Jezik     eng
Abstrakt     Mesentericin Y105 is a 37-residue bacteriocin produced by Leuconostoc mesenderoides Y105 that displays antagonistic activity against gram-positive bacteria such as Enterococcus faecalis and Listeria monocytogenes. It is closely related to leucocin A, an antimicrobial peptide containing beta-sheet and a-helical structures. To analyze structure-f'unctiun relationships and the mode of action of this bacreriocin, we generated a collection of mesentericin derivatives. Mutations were obtained mostly by PCR random mutagenesis, and the peptides were produced by an original system of heterologous expression recently described (D. Morisset and J. Frere, Biochimie 84:569-576, 2002). Ten derivatives were obtained displaying modifications at eight differeot positions in the mesentericin Y105 sequence. Purified peptides were incorporated into lysophosphatidylcholine micelles and analyzed by circular dichroism. The alpha-helical contents of these peptides were compared and related to their respective bactericidal activities. Moreover, studies of the intrinsic Huorescence of tryptophan residues naturally occurring at positions 18 and 37 revealed information about insertion of the peptides in micelles. A model for the mode of action of mesentericin Y105 and related bacteriocins is proposed.
Deskriptorji     LEUCONOSTOC
BACTERIOCINS
MUTATION
PHOSPHATIDYLCHOLINES
TRYPTOPHAN
PLASMIDS
CIRCULAR DICHROISM
POLYMERASE CHAIN REACTION