[DNA content in Escherichia coli mutants]

The content of DNA was assayed in Escherichia coli K-12 strains which underwent mutations in the genes pol A, uvr A, rec B during their cultivation in the Difco broth. The mutant in the gene rec B did not differ from the wild strain in the dynamics of DNA content. The mutants in the genes pol A and uvr A contained DNA three times as high as the wild strain cells at the beginning of the lag phase. Apparently, the genes pol A and uvr A are involved in the regulation of DNA content in the cells of E. coli.