title: New role for photoreversible pyrimidine dimers in induction of prototrophic mutations in excision-deficient Escherichia coli by UV light.
abstract: UV mutagenesis to His+ in certain recA441 lexA51 bacteria was not photoreversible, indicating that pyrimidine dimers are not target lesions. Photoreversibility was observed in recA+ lexA51 bacteria, showing that pyrimidine dimers are needed to activate the recA+ protein (unlike the recA441 protein) to perform a function in UV mutagenesis distinct from cleavage of the lexA repressor.
mesh_terms: D004260:DNA Repair; D004269:DNA, Bacterial / Q000528:radiation effects; D004926:Escherichia coli / Q000235:genetics*; D008027:Light; D009154:Mutation; D011108:Polymers; D011743:Pyrimidines / Q000378:metabolism*; D011938:Rec A Recombinases / Q000378:metabolism; D012097:Repressor Proteins / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D004269:DNA, Bacterial; D011108:Polymers; D011743:Pyrimidines; D012097:Repressor Proteins; D011938:Rec A Recombinases