Mutation Rates (×10−7) of pol3-01,eex Mutant Strains.

Rates of FOA or canavanine resistance (FOAr or Canr mutants per cell division) were determined by fluctuation analyses and maximum likelihood estimates using data from multiple independent experiments (except where noted). pol3-01,eex alleles are arranged from top to bottom according to the degree of mutator suppression as determined from rates of FOA resistance. Confidence intervals (95%) are in parentheses. A dash (–) indicates the mutation rate was not determined.aMutation rates were determined in two different strains: FOAr, BP4001; Canr, YP6.bMutation rates were determined in strain MP4.cpol3-01,eex alleles not analyzed: I616C, A677T, and P719T.dMutation rate from a single experiment.eThe fold-increase in mutation rate caused by loss of MSH6 (msh6Δ effect) was calculated by dividing each pol3-01,eex msh6Δ mutation rate by the corresponding pol3-01,eex MSH6 rate. On average, msh6Δ increased mutation rate 157-fold.