title: Nucleoid clumping is dispensable for the Dps-dependent hydrogen peroxide resistance in Staphylococcus aureus.
abstract: Dps family proteins have the ferroxidase activity that contributes to oxidative stress resistance. In addition, a part of Dps family proteins including Escherichia coli Dps and Staphylococcus aureus MrgA (metallo regulon gene A) bind DNA and induce the structural change of the nucleoid. We previously showed that a mutated MrgA with reduced ferroxidase activity was unable to contribute to the hydrogen peroxide (H2O2) and UV resistance in S. aureus, suggesting that the nucleoid clumping by MrgA is not sufficient for the resistance. However, it remained elusive whether the nucleoid clumping is dispensable for the resistance. Here, we aimed to clarify this question by employing the E. coli Dps lacking DNA-binding activity, DpsΔ18. Staphylococcal nucleoid was clumped by E. coli Dps, but not by DpsΔ18. H2O2 stress assay indicated that Dps and DpsΔ18 restored the reduced susceptibility of S. aureus ΔmrgA. Thus, we concluded that the staphylococcal nucleoid clumping is dispensable for the Dps-mediated H2O2 resistance. In contrast, Dps was unable to complement S. aureus ΔmrgA in the UV resistance, suggesting the MrgA function that cannot be compensated for by E. coli Dps.
authors.affiliation: Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 305-8575, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Ushijima
authors.affiliation: Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 305-8575, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Yoshida
authors.affiliation: Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba 305-8575, Japan.
authors.forename: Montecillo Jake Adolf
authors.initials: MJA
authors.lastname: Villanueva
authors.affiliation: Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan.|Center for Biotechnology, National Taiwan University, Taipei 10617, Taiwan, ROC.
authors.forename: Ryosuke L
authors.initials: RL
authors.lastname: Ohniwa
authors.affiliation: Faculty of Medicine, University of Tsukuba, Tsukuba 305-8575, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Morikawa
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D015964:Gene Expression Regulation, Bacterial; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D018384:Oxidative Stress; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006861:Hydrogen Peroxide