title: Hyper-recombination in dam mutants of Escherichia coli K-12.
abstract: 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.
mesh_terms: D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial / Q000378:metabolism; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000378:metabolism; D004926:Escherichia coli / Q000378:metabolism*; D005838:Genotype; D009154:Mutation; D011995:Recombination, Genetic; D013045:Species Specificity
chemical_list: D004248:DNA (Cytosine-5-)-Methyltransferases