Table 4.
mutL(E30A), mutL(N34H), and mutL(R176G) show a dominant negative increase in mutation frequency to native mutLa
| Genotype | Mutation rate × 10−9b | Relative mutation rate | Mutations per culture |
|---|---|---|---|
| wild type (PY79) | 3.7 (1.8–5.4) | 1.0 | 2.2 |
| amyE::PspacmutL+ | 3.5 (1.5–5.3) | 1.0 | 2.0 |
| mutL::spc | 159.0 (151.1–167.0) | 45.4 | 93.5 |
| mutL(A17V) | 4.1 (1.8–6.3) | 1.2 | 2.9 |
| mutL(G18A) | 2.3 (0.8–3.6) | 0.7 | 1.3 |
| mutL(P24L) | 3.7 (1.5–5.7) | 1.1 | 2.3 |
| mutL(E30A) | 10.8 (7.5–14.1) | 3.1 | 7.9 |
| mutL(N34H) | 102.3 (95.7–108.8) | 29.2 | 68.2 |
| mutL(S40A) | 2.6 (0.8–4.1) | 0.7 | 1.5 |
| mutL(N60S) | 2.7 (0.4–4.4) | 0.8 | 1.2 |
| mutL(G63R) | 2.3 (0.7–3.6) | 0.7 | 1.4 |
| mutL(K80E) | 6.2 (3.5–8.9) | 1.8 | 4.0 |
| mutL(G94S) | 1.6 (0.4–2.4) | 0.5 | 0.9 |
| mutL(S102R) | 5.0 (2.5–7.5) | 1.4 | 3.1 |
| mutL(R176G) | 48.5 (41.1–55.8) | 13.8 | 22.3 |
| mutL(G234V) | 5.2 (2.3–7.8) | 1.5 | 2.6 |
| mutL(R256C) | 2.9 (0.8–4.6) | 0.8 | 1.7 |
a
The mutation rate, relative mutation rate, and mutation per culture determined for each mutant allele when expressed in the presence of the wild-type mutL gene are shown. Mutation rates and mutations per culture were calculated by FALCOR (Fluctuation AnaLysis CalculatOR) using the MSS-MLE method (17, 23). Calculations were based on data collected through rifampin resistance by fluctuation analysis for 14 to 50 independent cultures per strain. Relative mutation rate reflects normalization of mutation rates to that obtained for Pspac mutL+.
b
The error shown in parentheses reflects the 95% confidence interval.