KINETICS OF GENETIC RECOMBINATION IN ESCHERICHIA COLI

Genetic recombination in Escherichia coli: the role of exonuclease I.

The indirect suppression of recB(-) and recB(-)recC(-) mutations by the sbcB(-) allele is caused by the loss of a nuclease active on denatured DNA. Results from enzyme purifications and studies with a specific antiserum demonstrate that the activity present in sbcB(+) strains, and lost in sbcB(-) strains, is exonuclease I. It is likely that sbcB is the structural gene for exonuclease I. The los...

:IBi Genetic recombination: the sexual process In Escherichia coli

Prevalence of Escherichia coli strains exhibiting genetic recombination.

The first bacterium to be tested by an efficient selective method for the occurrence of genetic recombination was strain K-12 of Bsche~icl~ia coli. Experiments with auxotroph mutants of this strain promptly gave conclusive, positive evidence of genetic exchanges between different mutant cells in mixed cultures (1, 2). However, subsequent attempts to obtain comparable results with a number of ot...

Gene Recombination in Escherichia coli

AKALYSIS of mixed cultures. sf nutritional mutants has revctlled the presence of new types which strongiy suggest the occurrence of a sexual process in the bacterium; EsciumcJ~ia coti. The mutants consist of strains which differ from their parent wild type, strain I.-l’& in lacking the ahilitv to synthesize growth-factors. . As a result of these dejiciencies they <ill only grow in media supplem...

Gene Recombination in Escherichia coli

rospect, (1) it must be judged to have been technically achievable at an earlier time with methods then available; (2) it must be judged to have been understandable, capable of being expressed in terms comprehensible to working scientists at the time; and (3) its implications must have been capable of having been appreciated. g In an era of Big Science, with goals such as the conquest of cancer...