title: Effect of chloramphenicol and the recB gene product on DNA metabolism in Escherichia coli K12 strains defective in DNA ligase.
abstract: We have examined DNA strand breakage, DNA degradation, and the rate of DNA synthesis in lig and lig-recB strains of Escherichia coli K12 incubated in the presence and absence of 3 mug/ml chloramphenicol. Substantial DNA strand breakage and DNA degradation is observed in the lig strain upon growth at 40 degrees C; however, such strand breakage and DNA degradation is not observed in th lig-recB strainl Incubation of the lig strain at 40 degrees C in the presence of 3 mug/ml chloramphenicol reduces the amount of DNA strand breakage and DNA degradation to the level observed in the lig-recB strain. Together, these results demonstrate that exonuclease V (the recBC gene product) is responsible for the increased DNA degradation associated with DNA ligase deficiency.
mesh_terms: D002701:Chloramphenicol / Q000494:pharmacology*; D002876:Chromosomes, Bacterial; D004247:DNA / Q000096:biosynthesis; D004260:DNA Repair; D004269:DNA, Bacterial / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology; D009154:Mutation; D011118:Polynucleotide Ligases / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D004269:DNA, Bacterial; D002701:Chloramphenicol; D004247:DNA; D011118:Polynucleotide Ligases