title: Mutations near the cleavage site of enterocin NKR-5-3B prepeptide reveal new insights into its biosynthesis.
abstract: Enterocin NKR-5-3B (Ent53B) is a 64-residue novel circular bacteriocin synthesized from an 87-residue prepeptide. Albeit through a still unknown mechanism, the EnkB1234 biosynthetic enzyme complex processes the prepeptide to yield its mature active, circular form. To gain insights into the key region/residue that plays a role in Ent53 maturation, several mutations near the cleavage site on the precursor peptide were generated. The interaction of the precursor peptide and EnkB1234 appeared to be hydrophobic in nature. At the Leu1 position, only mutations with helix structure-promoting hydrophobic residues (Ala, Ile, Val or Phe) were able to yield the mature Ent53B derivative. In this study, we also highlight the possible conformation-stabilizing role of the Ent53B leader peptide on the precursor peptide for its interaction with its biosynthetic enzyme complex. Any truncations of the leader peptide moiety interfered in the processing of the prepeptide. However, when propeptides of other circular bacteriocins (circularin A, leucocyclicin Q or lactocyclicin Q) were cloned at the C-terminus of the leader peptide, EnkB1234 could not process them to yield a mature bacteriocin. Taken together, these findings offer new perspectives in our understanding of the possible molecular mechanism of the biosynthesis of this circular bacteriocin. These new perspectives will help advance our current understanding to eventually elucidate circular bacteriocin biosynthesis. Understanding the biosynthetic mechanism of circular bacteriocins will materialize their application potential.
authors.affiliation: Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.|Present address: National Institute for Molecular Biology and Biotechnology (BIOTECH), University of the Philippines Los Baños, Laguna 4031, Philippines.
authors.forename: Rodney H
authors.initials: RH
authors.lastname: Perez
authors.affiliation: Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Sugino
authors.affiliation: Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Ishibashi
authors.affiliation: Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Zendo
authors.affiliation: Department of Fishery Products, Faculty of Fisheries, Kasetsart University, Chatuchak, Bangkok, Thailand.
authors.forename: Pongtep
authors.initials: P
authors.lastname: Wilaipun
authors.affiliation: Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Chatuchak, Bangkok 10900, Thailand.
authors.forename: Vichien
authors.initials: V
authors.lastname: Leelawatcharamas
authors.affiliation: Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Nakayama
authors.affiliation: Laboratory of Microbial Technology, Division of Systems Bioengineering, Department of Bioscience and Biotechnology, Faculty of Agriculture, Graduate School, Kyushu University, Fukuoka 812-8581, Japan.|Laboratory of Functional Food Design, Department of Functional Metabolic Design, Bio-Architecture Center, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Sonomoto
mesh_terms: D000595:Amino Acid Sequence / Q000235:genetics; D001430:Bacteriocins / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D001952:Bridged-Ring Compounds / Q000378:metabolism / Q000494:pharmacology; D003001:Cloning, Molecular; D013293:Enterococcus faecalis / Q000235:genetics / Q000378:metabolism; D016984:Enterococcus faecium / Q000235:genetics / Q000378:metabolism*; D008826:Microbial Sensitivity Tests; D009154:Mutation; D021382:Protein Sorting Signals / Q000235:genetics
chemical_list: D001430:Bacteriocins; D001952:Bridged-Ring Compounds; D021382:Protein Sorting Signals; C012306:enterocin