TABLE 4.
Base changes in leu revertants of the ΔmutSL mutY straina
| Revertant allele (day of expt) | Revertant sequenced | Position of mutation | Type of mutation | DNA change (result of mutation) |
|---|---|---|---|---|
| leuC (5) | 1 | ? | ? | ? |
| 2 | 427 | Transition | A→G (Arg→Gly) | |
| leuC (6) | 3 | 427 | Transition | A→G (Arg→Gly) |
| 4 | ? | ? | ? | |
| 5 | 427 | Transition | A→G (Arg→Gly) | |
| 6 | 427 | Transition | A→G (Arg→Gly) | |
| 7 | 427 | Transition | A→G (Arg→Gly) | |
| 8 | 427 | Transition | A→G (Arg→Gly) | |
| leuC (7) | 9 | 427 | Transition | A→G (Arg→Gly) |
| 10 | ? | ? | ? |
a
Chromosomal DNA was isolated (11) from Leu+ revertant colonies of the mutSL mutY strain collected from plates from adaptive mutagenesis assays during day 5, 6, or 7. A 303-bp fragment encompassing nucleotides 353 to 655 of the leuC ORF was amplified by PCR and sequenced as described in Materials and Methods. ?, mutations were not found in the sequenced leuC gene.