Table 2.
Kinetic parameters determined for ATC and BTC
| Enzyme | Substrate |
kcat (min−1) |
KM (μM) |
kcat/KM (min−1 M−1) |
RCEc |
Kss (μM) |
b |
|---|---|---|---|---|---|---|---|
| hBChE-7a | BTC | 46715 | 30.0 ± 2.5 | 1.56 × 109 | 0.74 | 1291 | 2.80 |
| hBChE b | BTC | 29500 ± 1100 | 14.0 ± 1.8 | 2.11 × 109 | 1.00 | 3010d | 3.36 |
| BChE-M47 | BTC | 355 ± 1300 | 24.8 ± 3.3 | 1.43 × 109 | 0.68 | 4983 | 2.99 |
| BChE-M48 | BTC | 334 ± 1030 | 28.5 ± 3.1 | 1.17 × 109 | 0.55 | 6760 | 3.11 |
| hBChE b | ATC | 20200 ± 910 | 57.0 ± 6.4 | 3.54 × 108 | 1.00 | 2890 | 2.47 |
| BChE-M47 | ATC | 19960 ± 830 | 38.5 ± 4.5 | 5.18 × 108 | 1.46 | 5000 | 3.03 |
| BChE-M48 | ATC | 17270 ± 640 | 41.9 ±5.3 | 4.12 × 108 | 1.16 | 4310 | 2.62 |
a
The kcat, KM, Kss, and b for hBChE-7 against BTC came from reference [32].
b
The kcat and KM for BChE expressed in CHO cells (hBChE) against BTC and ATC, Kss and b for hBChE against ATC came from in reference [49].
c
RCE refers to the relative catalytic efficiency (kcat/KM), i.e. the ratio of (kcat/KM) of the different BChE mutants against the same substrate.
d
The Kss and b for hBChE against BTC came from reference[50].