title: Gene cluster responsible for secretion of and immunity to multiple bacteriocins, the NKR-5-3 enterocins.
abstract: Enterococcus faecium NKR-5-3, isolated from Thai fermented fish, is characterized by the unique ability to produce five bacteriocins, namely, enterocins NKR-5-3A, -B, -C, -D, and -Z (Ent53A, Ent53B, Ent53C, Ent53D, and Ent53Z). Genetic analysis with a genome library revealed that the bacteriocin structural genes (enkA [ent53A], enkC [ent53C], enkD [ent53D], and enkZ [ent53Z]) that encode these peptides (except for Ent53B) are located in close proximity to each other. This NKR-5-3ACDZ (Ent53ACDZ) enterocin gene cluster (approximately 13 kb long) includes certain bacteriocin biosynthetic genes such as an ABC transporter gene (enkT), two immunity genes (enkIaz and enkIc), a response regulator (enkR), and a histidine protein kinase (enkK). Heterologous-expression studies of enkT and ΔenkT mutant strains showed that enkT is responsible for the secretion of Ent53A, Ent53C, Ent53D, and Ent53Z, suggesting that EnkT is a wide-range ABC transporter that contributes to the effective production of these bacteriocins. In addition, EnkIaz and EnkIc were found to confer self-immunity to the respective bacteriocins. Furthermore, bacteriocin induction assays performed with the ΔenkRK mutant strain showed that EnkR and EnkK are regulatory proteins responsible for bacteriocin production and that, together with Ent53D, they constitute a three-component regulatory system. Thus, the Ent53ACDZ gene cluster is essential for the biosynthesis and regulation of NKR-5-3 enterocins, and this is, to our knowledge, the first report that demonstrates the secretion of multiple bacteriocins by an ABC transporter.
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Ishibashi
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Himeno
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Masuda
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Rodney Honrada
authors.initials: RH
authors.lastname: Perez
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Shun
authors.initials: S
authors.lastname: Iwatani
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan zendo@agr.kyushu-u.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Zendo
authors.affiliation: Department of Fishery Products, Faculty of Fisheries, Kasetsart University, Bangkok, Thailand.
authors.forename: Pongtep
authors.initials: P
authors.lastname: Wilaipun
authors.affiliation: Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok, Thailand.
authors.forename: Vichien
authors.initials: V
authors.lastname: Leelawatcharamas
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Nakayama
authors.affiliation: Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka, Japan Department of Functional Metabolic Design, Bio-Architecture Center, Kyushu University, Fukuoka, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Sonomoto
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D053898:Biosynthetic Pathways; D001952:Bridged-Ring Compounds / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D016984:Enterococcus faecium / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D005516:Food Microbiology; D015964:Gene Expression Regulation, Bacterial; D005810:Multigene Family; D013785:Thailand
chemical_list: D000900:Anti-Bacterial Agents; D001952:Bridged-Ring Compounds; C012306:enterocin