Effect of the uvrD mutation on excision repair

Abstract

A pair of related Escherichia coli K-12 strains, one of which contains the uvrD101 mutation, were constructed and compared for ability to perform various steps in the excision repair of deoxyribonucleic acid damage inflicted by ultraviolet radiation. The results of this study indicated: (i) ultraviolet sensitivity in the uvrD101 mutant was greater than that of wild type but less than that measured in an incision-deficient uvrA mutant; (ii) host cell reactivation paralleled the survival data; (iii) postirradiation deoxyribonucleic acid degradation was virtually identical in the two strains; (iv) incision, presumably at the sites of pyrimidine dimers, proceeded normally in the uvrD101 strain; (v) excision of pyrimidine dimers was markedly reduced in both rate and extent in the uvrD101 mutant; (vi) the amount of repair resynthesis was the same in both strains, and there was no evidence of abnormally long repair patches in the uvrD mutant; and (vii) rejoining of incision breaks was slow and incomplete in the uvrD strain. These data suggest that the ultraviolet sensitivity conferred by the uvrD mutation arises from inefficient removal of pyrimidine dimers or from failure to close incision breaks. The data are compatible with the notion that the uvrD+ gene produce affects the conformation of incised deoxyribonucleic acid molecules.

Identification and characterization of the mutL and mutS gene products of Salmonella typhimurium LT2

“…We had previously found that the uvrD gene from S. typhimurium was able to complement E. coli uvrD mutants (27), and that its expression was regulated by the recA-lexA regulatory network of E. coli (28,39) in a fashion similar to that of the E. coli uvrD gene (36; H. M. Arthur and P. T. Emmerson, personal communication). The E. coli uvrD gene has been implicated as playing an important role in both mismatch repair and excision repair (13). The S. typhimurium mutH gene has also been cloned in this laboratory with a similar approach (S.-D. Tsen, P. P. Pang, and G. C. Walker, unpublished data).…”

Mutation of lysine-48 to arginine in the yeast RAD3 protein abolishes its ATPase and DNA helicase activities but not the ability to bind ATP.

“…However, we find that unlike the incision defective rad3-1 and rad3-2 mutants (Wilcox and Prakash, 1981), the rad3 Arg-48 mutant can carry out incision of DNA damaged by UV light but is unable to remove pyrimidine dimers from the incised DNA. In E. coli, this type of excision repair defect is seen in mutants of the UvrD gene (Kuemmerle and Masker, 1980), which encodes a DNA helicase (Kumura and Sekiguchi, 1984) that shows considerable sequence homology to RAD3 protein (Foury and Lahaye, 1987). The phenotypic and biochemical similarities between yeast RAD3 protein and the E. coli UvrD protein suggest that in excision repair, the two enzymes may play an evolutionarily conserved role in reactions subsequent to the nicking of damaged DNA.…”

Three rhamnosyltransferases responsible for assembly of the A‐band D‐rhamnan polysaccharide in Pseudomonas aeruginosa: a fourth transferase, WbpL, is required for the initiation of both A‐band and B‐band lipopolysaccharide synthesis

“…WbdA EcO9 , WbdB EcO9 and WbdC EcO9 from E. coli O9 (GenBank accession number D43637), MtfB S from Synechocystis species (D90911), Orf336 Sc from Salmonella choleraesuis (S22619), RfbU B from S. enterica serovar Typhimurium (S15310), RfbU Mj from Methanococcus jannaschii (U67601), GumH Xc from Xanthomonas campestris (U22511), Orf224 EcK12 from E. coli K-12 (L19537), RfbU VcO1 from Vibrio cholerae O1 (Y07788) and RfaK Nm from Neisseria meningitidis (U58765). and mismatch repair and may be involved in DNA recombination and replication (Kuemmerle and Masker, 1980;Arthur and Lloyd, 1980;Kuhn and Abdel-Monem, 1982;Modrich, 1991). The E. coli uvrD gene is found downstream of wecA±G (rfe±rff ) at 85 min on the K-12 chromosome (Meier and Mayer, 1985).…”