Figure 7
(A) Lac + reversion frequencies of MV6543 (MV4709 with pMS421) containing various OXR1 fragment-producing plasmids. Cells containing plasmids were grown overnight as described in the Methods section. All cultures contained 1 mM IPTG, except ones that contained pMV1266 and pKM407, which contained 0.1 mM IPTG (to prevent lethality that results from higher levels of expression of these OXR1 proteins). All cultures grew to saturation (2–4 x 109 cells/ml). The results are reported as the mean of 3–6 determinations for each strain; error bars report the standard error. A t-test analysis of the values reported for pKM398 and pKM406 determined that there is no significant difference between the two frequencies reported for these plasmids. (B) Diagram of the OXR1 fragment-producing plasmids used in the Lac + reversion assay.