TABLE 2.
Properties of Tsr A and G missense control cable mutants
| Tsr protein | Level of expression in UU2610a | Value in strain UU2567 (R− B−) |
Value in strain UU2700 (R+ B+) |
||||
|---|---|---|---|---|---|---|---|
| K1/2 (μM SER)b | Hill coefficientb | Kinase activityc | K1/2 (μM SER)b | Hill coefficientb | Kinase activityc | ||
| Wild type | 1.00 | 19 ± 1 | 17 ± 3 | 1.00 | 0.5 ± 0.2 | 3.0 ± 0.9 | 0.25 |
| Mutants | |||||||
| G213A | 0.80 | 79 ± 2 | 12 ± 4 | 0.80 | 4.1 ± 0.8 | 8.4 ± 5.2 | 0.25 |
| I214G | 0.75 | NR-ON | NR-ON | 1.15 | 13 ± 1 | 8.1 ± 1.3 | 1.50 |
| I214A | 1.15 | NR-ON | NR-ON | 1.25 | 1.5 ± 0.6 | 4.2 ± 0.8 | 1.05 |
| K215G | 0.85 | 37 ± 6 | 21 ± 10 | 0.95 | 0.7 ± 0.1 | 2.2 ± 1.3 | 0.30 |
| K215A | 1.00 | 28 | 7.7 | 0.80 | 0.5 ± 0.0 | 1.5 ± 0.1 | 0.30 |
| A216G | 0.75 | 24 ± 1 | 14 ± 2 | 0.60 | 0.9 ± 0.1 | 1.2 ± 0.0 | 0.30 |
| S217G | 1.70 | 17 ± 0 | 11 ± 1 | 0.25 | 0.6 ± 0.3 | 1.5 ± 0.5 | 0.35 |
| S217A | 1.15 | 9.3 ± 0 | 13 ± 8 | 0.85 | 0.7 ± 0.1 | 1.0 ± 0.1 | 0.40 |
Expression level of the mutant protein in strain UU2610 (R− B−). Values are rounded to the nearest 0.05 and normalized to that for wild-type Tsr.
Values with error ranges represent averages ± standard deviations of two or more independent FRET-based dose-response experiments (see Materials and Methods for details). Values above 10 were rounded to the nearest whole number. NR-ON, no detectable response to 10 mM serine, but high kinase activity.
Kinase activities are averages of two or more independent FRET-based assays, normalized to the value for wild-type Tsr in strain UU2567. All values are rounded to the nearest 0.05. Values in italics were determined by FRET changes after KCN treatment. See Materials and Methods for experimental details.