Table 1.
Generalized alcohol dehydrogenase and HAD activities of ABAD/ERAB *.
| Substrate or Alcohol | Km (mM) | Vmax (Units/mg) | Kcat a (s−1) | Catalytic Efficiency, Kcat/Km (M−1s−1) |
|---|---|---|---|---|
| Reduction of S-acetoacetyl-CoA | ||||
| S-acetoacetyl-CoA | 0.068 ± 0.020 | 430 ± 45 | 190 | 2.8 × 106 |
| Oxidation of alcohol substrate b | ||||
| 17β-Estradiol | 0.014 ± 0.006 | 23 ± 3 | 10 | 7.4 × 105 |
| Methanol | No activity | No activity | No activity | No activity |
| Ethanol | 1210 ± 260 | 2.2 ± 0.4 | 1.0 | 0.82 |
| Isopropanol | 150 ± 17 | 36 ± 2 | 16 | 110 |
| n-Propanol | 272 ± 62 | 4.2 ± 0.5 | 1.9 | 6.9 |
| n-butanol | 53 ± 6 | 9.0 ± 0.3 | 4.0 | 76 |
| Isobutanol | 56 ± 16 | 8.0 ± 0.7 | 3.6 | 64 |
| n-Pentanol | 18 ± 5 | 6.9 ± 0.4 | 3.1 | 170 |
| (±)-2-Octanol | 85 ± 17 | 245 ± 20 | 110 | 1300 |
| (+)-2-Octanol | 84 ± 16 | 102 ± 8 | 46 | 540 |
| (−)-2-Octanol | 43 ± 9.0 | 133 ± 23 | 60 | 1400 |
| n-Decanol | 14 ± 6.3 | 2.8 ± 0.5 | 1.3 | 90 |
* Reproduced from Table 13.1 of Ref. [27]. Data reported for a number of alcohols such as 2-octanol enantiomers and 17β-estradiol [19] were non-reproducible [4,7,21]. a Calculation based on 1 unit representing 1 μmol of product formed per min, and a molecular mass of the enzyme used for the calculation of Kcat was 26,926 Da because there was 1 active site per subunit. b Experiments were performed by incubating ERAB/HAD II with a range of concentrations of the indicated substrates in the presence of NAD+/NADH. Details of the experimental procedures are described in the text of Ref. [19].