title: Identification and three-dimensional structure of carnobacteriocin XY, a class IIb bacteriocin produced by Carnobacteria.
abstract: In this study, we report that CbnX (33 residues) and CbnY (29 residues) comprise a class IIb (two-component) bacteriocin in Carnobacteria. Individually, CbnX and CbnY are inactive, but together act synergistically to exert a narrow spectrum of activity. The structures of CbnX and CbnY in structure-inducing conditions were determined and strongly resemble other class IIb bacteriocins (i.e., LcnG, PlnEF, PlnJK). CbnX has an extended, amphipathic α-helix and a flexible C terminus. CbnY has two α-helices (one hydrophobic, one amphipathic) connected by a short loop and a cationic C terminus. CbnX and CbnY do not appear to interact directly and likely require a membrane-bound receptor to facilitate formation of the bacteriocin complex. This is the first class IIb bacteriocin reported for Carnobacteria.
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: Jeella Z
authors.initials: JZ
authors.lastname: Acedo
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: Kaitlyn M
authors.initials: KM
authors.lastname: Towle
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Lohans
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: Mark
authors.initials: M
authors.lastname: Miskolzie
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: Ryan T
authors.initials: RT
authors.lastname: McKay
authors.affiliation: Department of Chemistry, The King's University, Edmonton, AB, Canada.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Doerksen
authors.affiliation: Department of Chemistry, University of Alberta, Edmonton, AB, Canada.
authors.forename: John C
authors.initials: JC
authors.lastname: Vederas
authors.affiliation: Department of Chemistry, The King's University, Edmonton, AB, Canada.
authors.forename: Leah A
authors.initials: LA
authors.lastname: Martin-Visscher
mesh_terms: D001430:Bacteriocins / Q000737:chemistry* / Q000378:metabolism*; D056573:Carnobacterium / Q000737:chemistry / Q000378:metabolism*; D002942:Circular Dichroism; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D055503:Protein Multimerization; D017433:Protein Structure, Secondary
chemical_list: D001430:Bacteriocins
keywords: 
  Carnobacteria
  ; NMR solution structure; antimicrobial peptide; bacteriocin; class IIb; lactic acid bacteria