Fig. 5.

Photometric analysis of enzyme activity of D-LDH in cell-free extract. Determination of the activity of D-LDH from P. vulgatus pG106_ldhnP (a) and P. vulgatus pMM656_ldhnP (b) compared to wild type. Enzyme activities were assayed using cell-free extract by measuring the change in absorbance at 340 nm corresponding to the oxidation of NADH to NAD⁺ during the conversion of pyruvate to D-lactate. The experiment was performed in duplicate using the cell-free extract from two different cultures and the respective standard deviations are indicated by error bars. Black circles, P. vulgatus pG106_ldhnP; black triangles, P. vulgatus pMM656_ldhnP; gray circles, wild type