title: Isolation and characterization of a mutant of Escherichia coli K12 synthesizing DNA polymerase I and endonuclease I constitutively.
abstract: A mutant of Escherichia coli K12, highly resistant to ultraviolet radiation, has been isolated. Preliminary tests show that this mutant is also resistant to mitomycin C, nalidixic acid, fluorouracil and thymineless death. The mutant strain apparently repairs its damaged DNA more efficiently than wild-type E. coli K12 strains and, to do so, constitutively produces 35 times more DNA polymerase I and 12 times more endonuclease I than the wild-type strain.
mesh_terms: D004256:DNA Polymerase I / Q000096:biosynthesis*; D004260:DNA Repair; D004259:DNA-Directed DNA Polymerase / Q000096:biosynthesis*; D004352:Drug Resistance, Microbial; D004720:Endonucleases / Q000096:biosynthesis*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000528:radiation effects; D009154:Mutation; D014466:Ultraviolet Rays
chemical_list: D004256:DNA Polymerase I; D004259:DNA-Directed DNA Polymerase; D004720:Endonucleases