Table 2.
Kinetic Parameters of the Glycine Hinge Mutations
| Enzyme | Km (µM) | kcat(sec−1) | Ki(µM) | kcat/Km(M−1 sec−1) | Serine I 0.5b (µM) | Hill Coefficient |
|---|---|---|---|---|---|---|
| Native | 170 ± 50 | 2461 ± 281 | 950 ± 120 | 1.4 × 107 | 36 ± 6 | 1.8 ± 0.1 |
| G316V | 114 ± 4 | 1111 ± 30 | 2231 ± 190 | 1.0 × 107 | 23 ± 4 | 1.6 ± 0.1 |
| G317V | 165 ± 9 | 2111 ± 119 | 1110 ± 148 | 1.3 × 107 | 23 ± 3 | 1.5 ± 0.1 |
| G318V | 203 ± 23 | 2349 ± 177 | 1925 ± 437 | 1.2 × 107 | 166 ± 22 | 2.5 ± 0.1 |
| G316, 317V | 610 ± 95 | 2805 ± 310 | 380 ± 45 | 0.5 × 107 | 75 ± 17 | 1.7 ± 0.1 |
| G317, 318V | 220 ± 43 | 605 ± 27 | 1620 ± 402 | 0.3 × 107 | 53 ± 12 | 1.9 ± 0.1 |
| G316, 318V | 470 ± 43 | 2827 ± 197 | 220 ± 35 | 0.6 × 107 | 18 ± 5 | 1.9 ± 0.1 |
| G316,317, 318Va |
a
No detectable protein produced
b
All mutants are able to be inhibited by serine to < 95%.