Three distinct two-component systems are involved in resistance to the class I bacteriocins, Nukacin ISK-1 and nisin A, in Staphylococcus aureus

PLoS One. 2013 Jul 22;8(7):e69455. doi: 10.1371/journal.pone.0069455. Print 2013.

Abstract

Staphylococcus aureus uses two-component systems (TCSs) to adapt to stressful environmental conditions. To colonize a host, S. aureus must resist bacteriocins produced by commensal bacteria. In a comprehensive analysis using individual TCS inactivation mutants, the inactivation of two TCSs, graRS and braRS, significantly increased the susceptibility to the class I bacteriocins, nukacin ISK-1 and nisin A, and inactivation of vraSR slightly increased the susceptibility to nukacin ISK-1. In addition, two ABC transporters (BraAB and VraDE) regulated by BraRS and one transporter (VraFG) regulated by GraRS were associated with resistance to nukacin ISK-1 and nisin A. We investigated the role of these three TCSs of S. aureus in co-culture with S. warneri, which produces nukacin ISK-1, and Lactococcus lactis, which produces nisin A. When co-cultured with S. warneri or L. lactis, the braRS mutant showed a significant decrease in its population compared with the wild-type, whereas the graRS and vraSR mutants showed slight decreases. Expression of vraDE was elevated significantly in S. aureus co-cultured with nisin A/nukacin ISK-1-producing strains. These results suggest that three distinct TCSs are involved in the resistance to nisin A and nukacin ISK-1. Additionally, braRS and its related transporters played a central role in S. aureus survival in co-culture with the strains producing nisin A and nukacin ISK-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / genetics
  • Bacteriocins / biosynthesis
  • Bacteriocins / pharmacology*
  • Coculture Techniques
  • Drug Resistance, Bacterial / drug effects*
  • Gene Expression Regulation, Bacterial / drug effects
  • Lactococcus lactis / growth & development
  • Lactococcus lactis / metabolism
  • Mutation
  • Nisin / biosynthesis
  • Nisin / pharmacology*
  • Staphylococcus aureus / drug effects*
  • Staphylococcus aureus / genetics
  • Staphylococcus aureus / growth & development
  • Staphylococcus aureus / physiology*

Substances

  • ATP-Binding Cassette Transporters
  • Bacteriocins
  • nukacin ISK-1
  • Nisin
  • nisin A

Grants and funding

This study was supported in part by Grants-in-Aid for Young Scientists (B) from the Ministry of Education, Culture, Sports, Sciences, and Technology of Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.