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Title: Pyrimidine dimer excision in Escherichia coli strains deficient in exonucleases V and VII and in the 5'. -->. 3' exonuclease of DNA polymerase I. [uv radiation]

Abstract

An isogenic series of Escherichia coli strains deficient in various combinations of three 5' ..-->.. 3' exonucleases (exonuclease V, exonuclease VII, and the 5' ..-->.. 3' exonuclease of DNA polymerase I) was constructed and examined for the ability to excise pyrimidine dimers after uv irradiation. Although the recB and recC mutations (deficient in exonuclease V) proved to be incompatible with the polA(Ex) mutation (deficient in the 5' ..-->.. 3' exonuclease of DNA polymerase I), it was possible to reduce the level of the recB,C exonuclease by the use of temperature-sensitivite recB270 recC271 mutants. It was found that, by employing strains deficient in exonuclease V, postirradiation DNA degradation could be reduced and dimer excision measurements could be facilitated. Mutants deficient in exonuclease V were found to excise dimers at a rate comparable to that of the wild type. Mutants deficient in exonuclease V and the 5' ..-->.. 3' exonuclease of DNA polymerase I are slightly slower than the wild type at removing dimers accumulated after doses in excess of 40 J/m/sup 2/. However, although strains with reduced levels of exonuclease VII excised dimers at the same rate as the wild type, the addition of an exonuclease VII deficiency to a strainmore » with reduced levels of exonuclease V and the 5' ..-->.. 3' exonuclease of DNA polymerase I caused a marked decrease in the rate and extent of dimer excision. These observations support previous indications that the 5' ..-->.. 3' exonuclease of DNA polymerase I is important in dimer removal and also suggest a role for exonuclease VII in the excision repair process.« less

Authors:
 [1]; ;
  1. Albert Einstein Coll. of Medicine, Bronx, NY
Publication Date:
OSTI Identifier:
6367374
Resource Type:
Journal Article
Journal Name:
J. Bacteriol.; (United States)
Additional Journal Information:
Journal Volume: 137:1
Country of Publication:
United States
Language:
English
Subject:
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.; DNA; BIOCHEMICAL REACTION KINETICS; ESCHERICHIA COLI; BIOLOGICAL RADIATION EFFECTS; NUCLEASES; POLYMERASES; MUTANTS; PYRIMIDINES; ULTRAVIOLET RADIATION; AZINES; BACTERIA; BIOLOGICAL EFFECTS; ELECTROMAGNETIC RADIATION; ENZYMES; HETEROCYCLIC COMPOUNDS; KINETICS; MICROORGANISMS; NUCLEIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; PHOSPHOTRANSFERASES; RADIATION EFFECTS; RADIATIONS; REACTION KINETICS; TRANSFERASES; 560131* - Radiation Effects on Microorganisms- Basic Studies- (-1987)

Citation Formats

Chase, J W, Masker, W E, and Murphy, J B. Pyrimidine dimer excision in Escherichia coli strains deficient in exonucleases V and VII and in the 5'. -->. 3' exonuclease of DNA polymerase I. [uv radiation]. United States: N. p., 1979. Web.
Chase, J W, Masker, W E, & Murphy, J B. Pyrimidine dimer excision in Escherichia coli strains deficient in exonucleases V and VII and in the 5'. -->. 3' exonuclease of DNA polymerase I. [uv radiation]. United States.
Chase, J W, Masker, W E, and Murphy, J B. 1979. "Pyrimidine dimer excision in Escherichia coli strains deficient in exonucleases V and VII and in the 5'. -->. 3' exonuclease of DNA polymerase I. [uv radiation]". United States.
@article{osti_6367374,
title = {Pyrimidine dimer excision in Escherichia coli strains deficient in exonucleases V and VII and in the 5'. -->. 3' exonuclease of DNA polymerase I. [uv radiation]},
author = {Chase, J W and Masker, W E and Murphy, J B},
abstractNote = {An isogenic series of Escherichia coli strains deficient in various combinations of three 5' ..-->.. 3' exonucleases (exonuclease V, exonuclease VII, and the 5' ..-->.. 3' exonuclease of DNA polymerase I) was constructed and examined for the ability to excise pyrimidine dimers after uv irradiation. Although the recB and recC mutations (deficient in exonuclease V) proved to be incompatible with the polA(Ex) mutation (deficient in the 5' ..-->.. 3' exonuclease of DNA polymerase I), it was possible to reduce the level of the recB,C exonuclease by the use of temperature-sensitivite recB270 recC271 mutants. It was found that, by employing strains deficient in exonuclease V, postirradiation DNA degradation could be reduced and dimer excision measurements could be facilitated. Mutants deficient in exonuclease V were found to excise dimers at a rate comparable to that of the wild type. Mutants deficient in exonuclease V and the 5' ..-->.. 3' exonuclease of DNA polymerase I are slightly slower than the wild type at removing dimers accumulated after doses in excess of 40 J/m/sup 2/. However, although strains with reduced levels of exonuclease VII excised dimers at the same rate as the wild type, the addition of an exonuclease VII deficiency to a strain with reduced levels of exonuclease V and the 5' ..-->.. 3' exonuclease of DNA polymerase I caused a marked decrease in the rate and extent of dimer excision. These observations support previous indications that the 5' ..-->.. 3' exonuclease of DNA polymerase I is important in dimer removal and also suggest a role for exonuclease VII in the excision repair process.},
doi = {},
url = {https://www.osti.gov/biblio/6367374}, journal = {J. Bacteriol.; (United States)},
number = ,
volume = 137:1,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 1979},
month = {Mon Jan 01 00:00:00 EST 1979}
}