Fig. 4.

Effects of temperature on the activity and stability of the recombinant AcCR. Reaction conditions: a 0.25 mM NADH or 0.5 mM NAD⁺, 2 mL 50 mM citrate–phosphate buffer (pH 6.5 or 8.0), and 5 mM 4′-chloroacetophenone or 150 mM isopropanol were incubated at 20–55 °C for 5 min before adding 20 μL purified recombinant AcCR (about 0.008 mg of the purified enzyme), and the changes of absorbance for 3 min at 20–55 °C, respectively, were recorded; b 0.25 mM NADH, 2 mL 50 mM citrate–phosphate buffer (pH 6.5), and 5 mM 4′-chloroacetophenone were incubated for 5 min at 35 °C, then added 20 μL purified recombinant AcCR (about 0.008 mg of the purified enzyme, incubated at 20–55 °C), and the changes of absorbance for 3 min were recorded