Molecular and General Genetics MGG

, Volume 141, Issue 3, pp 189–206

The effect of lexA and recF mutations on post-replication repair and DNA synthesis in Escherichia coli K-12

  • Ann K. Ganesan
  • Patricia C. Seawell

DOI: 10.1007/BF00341799

Cite this article as:
Ganesan, A.K. & Seawell, P.C. Molec. gen. Genet. (1975) 141: 189. doi:10.1007/BF00341799


We have examined lexA1 uvr A6 and recF143 uvr Bδ derivatives of Escherichia coli K-12 for post-replication repair and DNA synthesis after UV irradiation. Compared to corresponding lex+ rec+strains, we found that the lexA and recF cells were defective in (1) conveting short DNA segments synthesized after irradiation to DNA of normal size; (2) synthesizing high molecular weight DNA after irradiation; (3) transferring pyrimidine dimers from irradiated DNA into unirradiated daughter strands. Our results support the hypothesis that after UV irradiation the formation of large DNA molecules in excision-deficient cells of E. coli depends directly or indirectly upon joining short DNA segments into longer strands, concomitant with the transfer of DNA from irradiated tamplates into unirradiated daughter strands. This process appears to require the activity of lexA and recF genes.

Copyright information

© Springer-Verlag 1975

Authors and Affiliations

  • Ann K. Ganesan
    • 1
  • Patricia C. Seawell
    • 1
  1. 1.Department of Biological SciencesStanford UniversityStanford

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