TABLE 3.

Mutant frequencies (mutants per 10⁸ cells) for dgt strains with lac alleles residing on the E. coli chromosome^a

Genotype	lac G·C→C·G	lac G·C→T·A	lac A·T→G·C
Wild type	0.02 ± 0.02	0.3 ± 0.1	0.02 ± 0.02
dgt	0.02 ± 0.02	0.3 ± 0.1	0.02 ± 0.02
mutL	0.08 ± 0.03	0.9 ± 0.2	13.5 ± 0.9
dgt mutL	0.09 ± 0.04	0.9 ± 0.2	16.9 ± 1.3

^aThe wild-type strains used were NR12403, NR12404, and NR12406 for the three lac alleles, respectively; the dgt strains were NR17538, NR17539, and NR17540; the mutL strains were NR17535, NR17536, and NR17537; and the dgt mutL strains were NR17541, NR17542, and NR17543 (Table 1). Mutant frequencies were determined as described in Materials and Methods.