title: IscR modulates catalase A (KatA) activity, peroxide resistance and full virulence of Pseudomonas aeruginosa PA14.
abstract: We have identified the iscR (PA3815) gene encoding an iron-sulfur cluster assembly regulator homologue as one of the genes required for peroxide resistance in Pseudomonas aeruginosa PA14. Here, we present the phenotypic characterization of an iscR deletion mutant in terms of KatA expression, stress responses, and virulence. The iscR null mutant exhibited reduced KatA activity at the posttranslational level, hypersensitivity to hydrogen peroxide, and virulence-attenuation in Drosophila melanogaster and mouse peritonitis models. These phenotypes were fully restored by multi-copy-based expression of katA. These results suggest that the requirement of IscR in P. aeruginosa is related to the proper activity of KatA, which is crucial for peroxide resistance and full virulence of this bacterium.
authors.affiliation: Department of Life Science, Sogang University, Seoul 121-742, Korea.
authors.forename: Seol-Hee
authors.initials: SH
authors.lastname: Kim
authors.forename: Bo-Young
authors.initials: BY
authors.lastname: Lee
authors.forename: Gee W
authors.initials: GW
authors.lastname: Lau
authors.forename: You-Hee
authors.initials: YH
authors.lastname: Cho
mesh_terms: D000818:Animals; D002374:Catalase / Q000378:metabolism*; D004331:Drosophila melanogaster; D005260:Female; D017353:Gene Deletion; D005816:Genetic Complementation Test; D006540:Herbicides / Q000494:pharmacology; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007501:Iron / Q000378:metabolism; D007506:Iron-Sulfur Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018384:Oxidative Stress; D010269:Paraquat / Q000494:pharmacology; D010538:Peritonitis / Q000209:etiology; D011189:Potassium Chloride / Q000378:metabolism; D011552:Pseudomonas Infections / Q000150:complications / Q000378:metabolism / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity*; D014774:Virulence
chemical_list: D006540:Herbicides; D007506:Iron-Sulfur Proteins; D011189:Potassium Chloride; D006861:Hydrogen Peroxide; D007501:Iron; D002374:Catalase; D010269:Paraquat