Isolation and characterization of temperature-sensitive mutants of the Staphylococcus aureus dnaC gene.
A protein encoded by the Staphylococcus aureus dnaC gene has 44% and 58% homology with Escherichia coli DnaB and Bacillus subtilis DnaC replicative DNA helicases, respectively. We identified five mutant strains whose temperature-sensitive colony formation phenotypes were complemented by the dnaC gene. DNA replication in these mutants has a fast-stop phenotype, indicating that the S. aureus dnaC gene encodes the replicative DNA helicase required for the elongation step. These mutants were also sensitive to UV irradiation, suggesting that the dnaC gene is involved in DNA repair. The number of viable mutant cells decreased at a non-permissive temperature, suggesting that S. aureus DnaC helicase is a promising target for antibiotics providing bactericidal effects.
Kaito
Chikara
C
Graduate School of Pharmaceutical Sciences, University of Tokyo, 3-1, 7-Chome, Hongo, Bunkyo-ku, 113-0033, Japan.
Kurokawa
Kenji
K
Hossain
Muktadir Shahid
MS
Akimitsu
Nobuyoshi
N
Sekimizu
Kazuhisa
K
D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D001483:Base Sequence; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics; D017931:DNA Primers; D004261:DNA Replication; D053488:DnaB Helicases; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins / Q000235:genetics*; D007700:Kinetics; D009154:Mutation; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013211:Staphylococcus aureus / Q000235:genetics* / Q000528:radiation effects; D013696:Temperature; D014466:Ultraviolet Rays
D001426:Bacterial Proteins; D017931:DNA Primers; C071702:DnaC protein, E coli; D029968:Escherichia coli Proteins; D004265:DNA Helicases; D053488:DnaB Helicases