The miaA Mutator Phenotype of Escherichia coli K-12 Requires Recombination Functions

miaA mutants, which contain A-37 instead of the ms(2)i(6)A-37 hypermodification in their tRNA, show a moderate mutator phenotype leading to increased GC→TA transversion. We show that the miaA mutator phenotype is dependent on recombination functions similar to, but not exactly the same as, those required for translation stress-induced mutagenesis.