title: The influence of the PO1A1 mutation upon recombination in Escherichia coli K12.
abstract: Genetic recombination in Escherichia coli is a highly regulated process involving multiple gene products. We have investigated the role of DNA polymerase I in this process by studying the effect of the po1A1 mutation upon DNA transfer and conjugation in otherwise isogenic suppressor-free strains of E. coli K-12. It was found that the po1A1 mutation greatly reduces recombination in Hfr crosses (a factor of 20 in Pol+ x Po1A1 crosses and more than a factor of 100 in Po1A1 X Po1A1 crosses). However, since the po1A1 mutation reduces the strains capacity to act as a recipient for an F-prime and the analysis of recombination transfer gradients revealed no differences between Po1+ and Po1- strains, it is concluded that DNA polymerase I probably affects the transfer and/or stability of donor DNA rather than the recombinational process itself.
mesh_terms: D003227:Conjugation, Genetic; D004256:DNA Polymerase I / Q000235:genetics*; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D005144:F Factor; D009154:Mutation; D011995:Recombination, Genetic
chemical_list: D004256:DNA Polymerase I; D004259:DNA-Directed DNA Polymerase