FIG. 5.

Effect of DCM on the expression of the polA′-lacZ fusion in the DM4-1445 polA mutant background. The β-galactosidase specific activity (sp. act.) arising from the polA′-lacZ transcriptional fusion was determined in cell extracts of M. dichloromethanicum DM4-1445 (circles) and DM4-1445(pME8112) (triangles) grown with MeOH as the carbon source with (filled symbols) and without (open symbols) prior treatment with 10 mM DCM at an OD₆₀₀ of 0.05 and expressed as a function of the optical density of the cultures at the time of cell harvest. Error bars, standard errors of triplicate measurements.