Table 1.
The half-saturation (Michaelis) coefficient (Km), catalytic rate constant (kcat) and catalytic efficiency (kcat/Km) values for the purified CN1E1 esterase for representative, structurally diverse esters. Three independent experiments at 40°C and pH 8.0 (5 mM EPPS buffer) were performed for each parameter, and the data are shown with the standard deviation. The parameters were determined using conditions and methods described previously (Alcaide et al., 2013)
| Substrate | Km (mM) | kcat (s-−1) | kcat/Km (s−1 M−1) |
|---|---|---|---|
| pNP-acetate | 0.19 ± 0.01 | 7.52 ± 0.21 | 39 867 |
| Methyl phenanthrene-9-carboxylate | 0.53 ± 0.03 | 4.76 ± 0.29 | 8 947 |
| Naphthalene carboxylic acid methyl ester | 0.71 ± 0.06 | 5.82 ± 0.24 | 8 156 |
| Tri-O-acetyl-D-glucal | 1.08 ± 0.05 | 7.81 ± 0.47 | 7 237 |
| Phenyl acetate | 0.94 ± 0.05 | 5.75 ± 0.40 | 6 096 |
| Benzoic acid, 4-formyl-, phenylmethyl ester | 0.64 ± 0.06 | 3.61 ± 0.17 | 5 626 |
| Protocatechuic acid ethyl ester | 1.14 ± 0.06 | 5.49 ± 0.33 | 4 798 |
| 2,5-Dihydroxycinnamic acid methyl ester | 1.06 ± 0.06 | 5.07 ± 0.17 | 4 790 |
| Butyl acetate | 2.10 ± 0.17 | 8.76 ± 0.48 | 4 167 |
| Anthracene-2-carboxylic acid methyl ester | 1.47 ± 0.05 | 5.59 ± 0.20 | 3 802 |
| Methyl phenanthrene-3-carboxylate | 1.60 ± 0.09 | 4.85 ± 0.18 | 3 022 |
| Dimethyl phthalate | 1.59 ± 0.10 | 4.75 ± 0.17 | 2 998 |
| Methyl bromoacetate | 1.70 ± 0.09 | 4.01 ± 0.14 | 2 358 |
| Triacetin | 1.64 ± 0.08 | 1.82 ± 0.10 | 1 109 |