Molecular and General Genetics MGG

, Volume 149, Issue 3, pp 273–277

Hyper-recombination in dam mutants of Escherichia coli K-12

  • M. G. Marinus
  • E. Bruce Konrad


F-prime heterogenotes of dam-3 bacteria segregate F-prime homogenotes at a frequency 30–200 times higher than the isogenic dam+ strain. A hyperrecombination mutant which shows increased recombination between chromosomal duplications was characterized as a dam mutant. The dam-3 allele causes a reduction in linkage of proximal unselected markers in transconjugants and increases the recombination frequency between a pair of closely linked markers. It is concluded that dam mutations confer a hyperrecombination phenotype to the cell.


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Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • M. G. Marinus
    • 1
  • E. Bruce Konrad
    • 2
  1. 1.Dept. of PharmacologyUniversity of Massachusetts Medical SchoolWorcester
  2. 2.Dept. of Biochemical Pharmacology, N.I.A.M.D.D.National Institutes of HealthBethesda

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