Exonuclease requirements for recombination of λ phage in recD mutants of Escherichia coli
نویسندگان
چکیده
Recombination of λ red gam phage in recD mutants is unaffected by inactivation of RecJ exonuclease. Since nucleases play redundant roles in E. coli, we inactivated several exonucleases in a recD mutant and discovered that 5’-3’ exonuclease activity of RecJ and exonuclease VII is essential for λ recombination, whereas exonucleases of 3’-5’ polarity are dispensable. The implications of the presented data on current models for recombination initiation in E. coli are discussed.
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Properties of Escherichia coli expressing bacteriophage P22 Abc (anti-RecBCD) proteins, including inhibition of Chi activity.
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