title: Involvement of DNA helicases in chromate resistance by Pseudomonas aeruginosa PAO1.
abstract: Chromate-hypersensitive mutants of the Pseudomonas aeruginosa PAO1 strain were isolated using transposon insertion mutagenesis. Comparison of the nucleotide sequences of the regions interrupted within the PAO1 genome showed that mutant strains GGP-64 and AJ-22 were affected in open reading frames PA0967 and PA5345, which correspond to the ruvB and recG genes, respectively. These genes encode helicases RuvB and RecG involved in DNA replication, recombination and repair. The chromate resistance phenotype in mutants GGP-64 and AJ-22 was restored by cosmids bearing wild type ruvB or recG genes, respectively. Also, both mutant strains showed an increased susceptibility to the toxic oxyanions tellurite and selenite as well as to mitomycin C, but not to arsenite, paraquat and hydrogen peroxide. It was concluded that P. aeruginosa RuvB and RecG helicases are involved in repairing DNA damage caused by chromate or its derivatives.
authors.affiliation: Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana, Edificio B-3, Ciudad Universitaria, 58030 Morelia, Michoacan, México.
authors.forename: Alma T
authors.initials: AT
authors.lastname: Miranda
authors.forename: Marcela V
authors.initials: MV
authors.lastname: González
authors.forename: Gabriela
authors.initials: G
authors.lastname: González
authors.forename: Eréndira
authors.initials: E
authors.lastname: Vargas
authors.forename: Jesús
authors.initials: J
authors.lastname: Campos-García
authors.forename: Carlos
authors.initials: C
authors.lastname: Cervantes
mesh_terms: D001483:Base Sequence; D002840:Chromates / Q000633:toxicity*; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003360:Cosmids; D004265:DNA Helicases / Q000235:genetics*; D004260:DNA Repair; D004269:DNA, Bacterial / Q000235:genetics; D004305:Dose-Response Relationship, Drug; D004352:Drug Resistance, Microbial / Q000235:genetics*; D005798:Genes, Bacterial; D016680:Genome, Bacterial; D016254:Mutagenesis, Insertional; D009154:Mutation; D016366:Open Reading Frames; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D017422:Sequence Analysis, DNA
chemical_list: D002840:Chromates; D004269:DNA, Bacterial; D004265:DNA Helicases