title: Bacitracin sensing and resistance in Staphylococcus aureus.
abstract: Bacterial two-component systems (TCSs) have been demonstrated to be associated with not only the expression of virulence factors, but also the susceptibility to antibacterial agents. In Staphylococcus aureus, 16 types of TCSs have been identified. We previously found that the inactivation of one uncharacterized TCS (designated as BceRS, MW gene ID: MW2545-2544) resulted in an increase in susceptibility to bacitracin. In this study, we focused on this TCS and tried to identify the TCS-controlled factors affecting the susceptibility to bacitracin. We found that two ABC transporters were associated with the susceptibility to bacitracin. One transporter designated as BceAB (MW2543-2542) is downstream of this TCS, while another (formerly designated as VraDE: MW2620-2621) is separate from this TCS. Both transporters showed homology with several bacitracin-resistance factors in Gram-positive bacteria. Inactivation of each of these two transporters increased the susceptibility to bacitracin. Expressions of these transporters were significantly increased by the addition of bacitracin, while this induction was not observed in the TCS-inactivated mutant. These results indicate that this TCS senses bacitracin, and also positively regulates the expression of two ABC transporters.
authors.affiliation: Department of Oral Microbiology, Kagoshima University Graduate School of Medical and Dental Sciences, Japan.
authors.forename: Yuuma
authors.initials: Y
authors.lastname: Yoshida
authors.forename: Miki
authors.initials: M
authors.lastname: Matsuo
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Oogai
authors.forename: Fuminori
authors.initials: F
authors.lastname: Kato
authors.forename: Norifumi
authors.initials: N
authors.lastname: Nakamura
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Sugai
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Komatsuzawa
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001414:Bacitracin / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D024881:Drug Resistance, Bacterial; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001414:Bacitracin