TABLE 3.
Reversion of tandem duplications
| Mutant | Mutationa | Mean no. of revertants/ 108 CFU (SD) |
|---|---|---|
| JDS66 | TD, 6 bp | 3.9 (5.2) |
| JDS178 | TD, 19 bp | 2,850 (990) |
| JDS12 | TD, 22 bp | 5,750 (6,800) |
| JDS18 | TD, 36 bp | 20,000 (6,700) |
| JDS64b | TD, 43 bp | <0.48 |
| JDS21 | −C | <0.35 |
| JDS36 | −G | 0.46 (0.68) |
| JDS10 | +G | <3.1 |
| JDS37 | +G | 0.40 (0.97) |
| JDS183 | +T | <0.24 |
a
TD, tandem duplication (the 6-bp duplication was of nt 346 to 351; the others were those diagrammed in Fig. 1); −C, C deleted; +G, G added.
b
It could not be ruled out that in the clone used for these experiments, the original duplication had mutated to a nonrevertable form.