FIG. 1.

Synthesis of CO-DH in the WT and ΔCutRmt strains of Mycobacterium sp. strain JC1 grown on various growth substrates. The strains were grown to an OD₆₀₀ of 0.7 in SMB medium supplemented with 0.2% (wt/vol) glucose (glucose), 0.2% (wt/vol) glucose plus 30% (vol/vol) CO (glucose + CO), or 30% (vol/vol) CO (CO). The ΔCutRmt with pNBV1 grew with CO as the sole source of carbon so slowly that the mutant was grown to an OD₆₀₀ of 0.3. (A) CO-DH activities. The specific activity indicates nanomoles of INT reduced per milligram protein per minute. The black and gray bars indicate the enzyme activities detected in the WT and ΔCutRmt strains, respectively. The error bars indicate the standard deviation of the values obtained from two independent determinations. (B) Activity staining of CO-DH. Crude extracts (10 μg) were subjected to nondenaturing PAGE on 7.5% (wt/vol) acrylamide gel, and the gel was subsequently subjected to activity staining. (C) Western blot analysis with a polyclonal CO-DH antibody. Crude extracts (10 μg) were subjected to denaturing SDS-PAGE on 12.5% (wt/vol) acrylamide gel. The bands represent the large subunit of CO-DH. “+” and “-” indicate the presence or absence, respectively, of the corresponding plasmids in Mycobacterium sp. strain JC1 strains.