DNA polymerase I-mediated ultraviolet repair synthesis in toluene-treated Escherichia coli

Journal Article · Fri Feb 10 04:00:00 EST 1978 · J. Biol. Chem.; (United States)

OSTI ID:6654137

Dorson, J W; Moses, R E

DNA synthesis after ultraviolet irradiation is low in wild type toluene-treated cells. The level of repair incorporation is greater in strains deficient in DNA polymerase I. The low level of repair synthesis is attributable to the concerted action of DNA polymerase I and polynucleotide ligase. Repair synthesis is stimulated by blocking ligase activity with the addition of nicotinamide mononucleotide (NMN) or the use of a ligase temperature-sensitive mutant. NMN stimulation is specific for DNA polymerase I-mediated repair synthesis, as it is absent in isogenic strains deficient in the polymerase function or the 5' leads to 3' exonuclease function associated with DNA polymerase I. DNA synthesis that is stimulated by NMN is proportional to the ultraviolet exposure at low doses, nonconservative in nature, and is dependent on the uvrA gene product but is independent of the recA gene product. These criteria place this synthesis in the excision repair pathway. The NMN-stimulated repair synthesis requires ATP and is N-ethylmaleimide-resistant. The use of NMN provides a direct means for evaluating the involvement of DNA polymerase I in excision repair.

• Research Organization: Baylor College of Medicine, Houston
• OSTI ID: 6654137
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 253:3; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

560112 -- Radiation Effects on Biochemicals-- In Microorganisms-- (-1987)
560130* -- Radiation Effects on Microorganisms
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AROMATICS
BACTERIA
BIOLOGICAL EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
DNA
DOSE-RESPONSE RELATIONSHIPS
DRUGS
ELECTROMAGNETIC RADIATION
ENZYMES
ESCHERICHIA COLI
HYDROCARBONS
INHIBITION
LIGASES
MICROORGANISMS
MUTANTS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
POLYMERASES
RADIATIONS
RECOVERY
REPAIR
STIMULATION
SYNTHESIS
TOLUENE
ULTRAVIOLET RADIATION