Table 3.

The relative activity of the recombinant AcCR to catalyze the oxidation of alcohols and reduction of ketones

Substrate	Structure	Relative activity (%)	Substrate	Structure	Relative activity (%)
Isopropanol		45.4
1-Phenethyl alcohol		Nd	Acetophenone		9.2
1-(4-Methylphenyl)ethanol		16.6	4-Methylacetophenone		16.5
2-Methoxyphenethyl alcohol		1.9	2-Methoxyacetophenone		3.1
3-Methoxyphenethyl alcohol		7.7	3-Methoxyacetophenone		10.7
4-Methoxyphenethyl alcohol		11.6	4-Methoxyacetophenone		5.1
3,3-Dimethyl-2-butanol		36.5	3,3-dimethyl-2-butanone		47.5
1-(Trimethylsilyl)-ethanol		Nd	1-(Trimethylsilyl)ethanone		156.5
4-(Trimethylsilyl)-3-butyn-2-ol		2.9	4-(Trimethylsilyl)-3-butyn-2-one		114.4
Methyl 3-hydroxybutyrate		13.1	Methyl acetoacetate		81.1
Ethyl 3-hydroxybutyrate		6.2	Ethyl acetoacetate		52.1
Ethyl (R)-4-chloro-3-hydroxybutyrate		Nd	Ethyl-4-chloroacetoacetate		120.6
Ethyl (S)-4-chloro-3-hydroxybutyrate		Nd
1-(4-Fluorophenyl)ethanol		55.1	4-Fluoroacetophenone		85.1
1-(4-Chlorophenyl)ethanol		52.3	4-Chloroacetophenone		100.0
1-(4-Bromophenzyl) alcohol		44.2	4-Bromoacetophenone		117.1
1-(4-Nitrophenzyl) alcohol		49.6	4-Nitroacetophenone		98.7
2-Pentanol		98.6	2-pentanone		158.6
2- (R)-Octanol		107.7	2-Octanone		87.58
2- (S)-Octanol		2.9
Ethyl 2-hydroxy-4-phenylbutyrate		2.3	Ethyl 2- oxo-4-phenylbutyrate		35.8

Reaction conditions: for oxidation reaction (a) 0.5 mM NAD⁺, 2 mL 50 mM Tris–HCl buffer (pH 8.5), 50 mM alcohol compound incubated at 45 °C for 5 min before adding 20 μL purified recombinant AcCR (about 0.008 mg the purified enzyme), recorded the changes of absorbance for 3 min at 45 °C; for reduction reaction (b) 0.25 mM NADH, 2 mL 50 mM citrate–phosphate buffer (pH 6.5), 50 mM carbonyl compound at 35 °C for 5 min before adding 20 μL purified recombinant AcCR (about 0.008 mg the purified enzyme) recorded the changes of absorbance for 3 min at 35 °C