Ultrafast chemical repair of DNA single and double strand break precursors in irradiated V79 cells

Journal Article · Wed Jan 01 00:00:00 EST 1986 · Basic Life Sci.; (United States)

DOI:https://doi.org/10.1007/978-1-4615-9462-8_10· OSTI ID:5003385

Michael, B D; Davies, S; Held, K D

The fast kinetics of reactions of free radical precursors of DNA single strand breaks (ssb) and double strand breaks (dsb) have been determined in Chinese hamster V79 cells by fast mixing and irradiation methods using the alkaline unwinding technique to assay breaks. Fast chemical repair of oxygen-dependent ssb and dsb precursors was observed and approached completion within 10-20 ms of irradiation. Treatment of cells with the glutathione synthesis blocking agent, buthionine sulphoximine, showed that approximately half of the chemical repair was attributable to intracellular non-protein thiols. The nature of the residual repair is obscure, but it is apparently not attributable to non-protein thiols. Similar repair rates and thiol dependences were also found for cell kill. With all three endopoints, oxygen competes with and blocks the chemical repair.

• Research Organization: Cancer Research Campaign Gray Laboratory, Middlesex, England
• OSTI ID: 5003385
• Journal Information: Basic Life Sci.; (United States), Journal Name: Basic Life Sci.; (United States)
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
DNA REPAIR
BIOCHEMICAL REACTION KINETICS
CHO CELLS
DNA
OXYGEN
RADIOINDUCTION
STRAND BREAKS
THIOLS
ANIMAL CELLS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
ELEMENTS
KINETICS
NONMETALS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
REACTION KINETICS
RECOVERY
REPAIR
560111* - Radiation Effects on Biochemicals- In Vitro- (-1987)