Purification and some characteristics of enterocin ON-157, a bacteriocin produced by Enterococcus faecium NIAI 157.
Bacteriocin-like activity (BLA) was screened in 690 strains of lactic acid bacteria isolated from plant materials such as silages and fermented vegetables. Among them, a strain identified as Enterococcus faecium NIAI 157 showed a clear BLA against the indicator strain, Ent. faecium IFO 13712. The proteinaceous nature and antimicrobial activity against closely related species strongly indicated that this BLA was a bacteriocin and was designated enterocin ON-157. The bacteriocin activity of this strain was extracellularly produced in the logarithmic growth phase in MRS broth and purified by ultrafiltration, ammonium sulphate precipitation and cation-exchange chromatography. Purified enterocin ON-157 had a molecular weight of approximately 2500 Da in SDS-PAGE analysis and was easily inhibited by treatment with alpha-amylase and proteolytic enzymes. Enterocin ON-157 had a bactericidal mode of action and inhibited the growth of the enterococci, Lactobacillus sake and Listeria monocytogenes. Enterococcus faecium NIAI 157 harboured two plasmids, 49.0 kb and 43.7 kb, and a variant missing a larger plasmid by curing with novobiocin lost the bactriocin activity.
Ohmomo
S
S
National Institute of Animal Industry, Tsukuba, Ibaraki, Japan.
Murata
S
S
Katayama
N
N
Nitisinprasart
S
S
Kobayashi
M
M
Nakajima
T
T
Yajima
M
M
Nakanishi
K
K
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001430:Bacteriocins / Q000302:isolation & purification* / Q000494:pharmacology; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D016984:Enterococcus faecium / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D007778:Lactobacillus / Q000187:drug effects / Q000254:growth & development; D008089:Listeria monocytogenes / Q000187:drug effects / Q000254:growth & development; D008826:Microbial Sensitivity Tests; D009561:Nisin / Q000494:pharmacology; D010957:Plasmids
D000900:Anti-Bacterial Agents; D001430:Bacteriocins; C407313:enterocin ON-157; D009561:Nisin