title: Escherichia coli strains containing mutations in the structural gene for topoisomerase I are recombination deficient.
abstract: Mutations in the gene encoding topoisomerase I of Escherichia coli were tested for their effect on plasmid recombination. Recombination was decreased 1,000-fold at 30 and 37 degrees C and occurred at approximately wild-type frequencies at 42 degrees C. The suppression of topA mutations at 42 degrees C did not appear to be a result of increased topoisomerase I activity at 42 degrees C.
mesh_terms: D004264:DNA Topoisomerases, Type I / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D005838:Genotype; D009154:Mutation; D010957:Plasmids; D011995:Recombination, Genetic
chemical_list: D004264:DNA Topoisomerases, Type I