The disappearance of thymine dimers from DNA. An error-correcting mechanism

Journal Article · Sat Feb 01 04:00:00 EST 1964 · Proceedings of the National Academy of Sciences of the United States of America

DOI:https://doi.org/10.1073/pnas.51.2.226· OSTI ID:4121186

Setlow, R. B.; Carrier, W. L.

The state of thymine dimers during the time in which resistant strains of Escherichia coli recover from uvinduced delays in DNA synthesis was investigated. Five strains of E. coli were labeled by growth in Mg medium containing tritiated thymidine. At various times after uv irradiation (200 ergs/ mm² at 265 m μ ), 1 ml aliquots of cell suspension were centrifuged, trichloracetic acid (TCA) supernatants were removed, and samples were prepared for chromatographic and counting procedures. Photoreactivating illumination was provided by black-light lamps. The radiation dose used stopped DNA synthesis and virtually eliminated colony-formation in two of the five strains. In the other three strains DNA synthesis was inhibited for 60 minutes and colony formation yields were reduced to 0.1 to 10 percent. The dimers disappeared from the acid- soluble fraction of the cells and appeared in the oligonucleotides. In a sensitive strain the dimers remained in the insoluble phase and were photoreactivable. Thus, the onset of DNA synthesis is associated with thymine dimer removal, which is suggested to be one step in cell recovery.

• Research Organization: Oak Ridge National Lab., Tenn.
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-011774
• OSTI ID: 4121186
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Issue: 2 Vol. 51; ISSN 0027-8424
• Publisher: National Academy of Sciences, Washington, DC (United States)
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ACETIC ACID
BACTERIA
CENTRIFUGATION
CHROMATOGRAPHY
DNA
ESCHERICHIA COLI
LABELLED COMPOUNDS
LIGHT
METABOLISM
NUCLEIC ACIDS
ORGANIC NITROGEN COMPOUNDS
PHOTOCHEMISTRY
RADIATION DOSES
RADIATION EFFECTS
RECOVERY
SOLVENT EXTRACTION
THYMINE
TRACER TECHNIQUES
TRITIUM
ULTRAVIOLET RADIATION