Whole-genome sequencing of mutants with increased resistance against the two-peptide bacteriocin plantaricin JK reveals a putative receptor and potential docking site

PLoS One. 2017 Sep 20;12(9):e0185279. doi: 10.1371/journal.pone.0185279. eCollection 2017.

Abstract

By whole-genome sequencing of resistant mutants, a putative receptor for plantaricin JK, a two-peptide bacteriocin produced by some Lactobacillus plantarum strains, was identified in Lactobacillus plantarum NCFB 965 and Weissella viridescens NCFB 1655. The receptors of the two species had 66% identical amino acid sequences and belong to the amino acid-polyamine-organocation (APC) transporter protein family. The resistant mutants contained point mutations in the protein-encoding gene resulting in either premature stop codons, leading to truncated versions of the protein, or single amino acid substitutions. The secondary structure of the W. viridescens protein was predicted to contain 12 transmembrane (TM) helices, a core structure shared by most members of the APC protein family. The single amino acid substitutions that resulted in resistant strains were located in a confined region of the protein that consists of TM helix 10, which is predicted to be part of an inner membrane pore, and an extracellular loop between TM helix 11 and 12. By use of template-based modeling a 3D structure model of the protein was obtained, which visualizes this mutational hotspot region and further strengthen the hypothesis that it represents a docking site for plantaricin JK.

MeSH terms

  • Bacterial Proteins / chemistry
  • Bacterial Proteins / metabolism*
  • Bacteriocins / chemistry
  • Bacteriocins / metabolism
  • Bacteriocins / pharmacology*
  • Binding Sites
  • Drug Resistance, Bacterial / drug effects
  • Drug Resistance, Bacterial / genetics
  • Genome, Bacterial
  • Lactobacillus plantarum / genetics*
  • Molecular Docking Simulation
  • Mutation
  • Weissella / drug effects
  • Weissella / genetics*

Substances

  • Bacterial Proteins
  • Bacteriocins
  • plantaricin JK

Grant support

This work was supported by the Molecular Life Science initiative at the University of Oslo. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.