TABLE 2.
Kinetic data for wild type and a range of amino acid substitutions at positions 103 and 389
Data are shown as mean ± S.E. for n = 6 experiments and are representative of two preparations of wild-type protein and one preparation of each mutant protein.
| GCK | Hydro- | S0.5 | nH | ATPKm | Kcat | RAI | GSIS threshold |
|---|---|---|---|---|---|---|---|
| mm | mm | s−1 | mm | ||||
| Wild type | Phobe | 7.5 ± 0.1 | 1.6 ± <0.1 | 0.4 ± <0.1 | 62.9 ± 1.2 | 1.0 | 5.0 |
| V389L | Phobe | 3.5 ± 0.1 | 1.6 ± <0.1 | 0.5 ± <0.1 | 67.8 ± 1.6 | 6.0 | 2.9 |
| V389C | Phobe | 8.3 ± 0.3 | 1.5 ± <0.1 | 0.5 ± <0.1 | 58.5 ± 2.4 | 0.8 | 5.0 |
| V389S | Phobe | 23.9 ± 2.5 | 1.3 ± <0.1 | 0.7 ± <0.1 | 39.9 ± 2.1 | <0.1 | 6.5 |
| V389P | Phobe | 39.4 ± 0.6 | 1.8 ± <0.1 | 0.6 ± <0.1 | 31.3 ± 0.3 | <0.1 | 6.8 |
| V389D | Phile | 78.6 ± 4.5 | 1.5 ± <0.1 | 1.5 ± 0.1 | 10.3 ± 1.1 | <0.1 | 7.1 |
| V389R | Phile | 68.8 ± 0.8 | 1.6 ± <0.1 | 0.5 ± <0.1 | 42.3 ± 0.4 | <0.1 | 6.8 |
| T103S | Phobe | 3.3 ± 0.1 | 1.6 ± <0.1 | 0.4 ± <0.1 | 59.2 ± 1.7 | 8.4 | 2.9 |
| T103P | Phobe | 6.0 ± 0.1 | 1.9 ± <0.1 | 0.6 ± <0.1 | 51.9 ± 0.7 | 1.2 | 4.7 |
| T103Y | Phobe | 9.1 ± 1.0 | 1.3 ± 0.1 | 0.4 ± <0.1 | 39.0 ± 0.9 | 0.9 | 5.5 |
| T103C | Phobe | 11.2 ± 0.2 | 1.5 ± <0.1 | 0.5 ± <0.1 | 52.3 ± 1.4 | 0.3 | 5.7 |
| T103I | Phobe | 24.9 ± 0.6 | 1.7 ± <0.1 | 0.6 ± <0.1 | 68.1 ± 0.1 | <0.1 | 6.7 |
| T103N | Phile | 5.8 ± 0.1 | 1.6 ± <0.1 | 0.5 ± <0.1 | 51.5 ± 1.1 | 1.2 | 4.5 |
| T103K | Phile | 7.5 ± 0.3 | 1.3 ± <0.1 | 0.4 ± <0.1 | 25.6 ± 0.7 | 0.9 | 5.6 |