TABLE 2.
Summary of kinetic constants for Ubc5A C-terminal mutants
| kcata | [S]0.5 | nH | |
|---|---|---|---|
| s−1 | nm | ||
| Ubc5A (wt)b | 4.5 ± 0.8 × 10−3 | 410 ± 10 | 5.1 ± 0.3 |
| Ubc5AΔ138 | NAc | NA | NA |
| Ubc5AR139A | 8.3 ± 0.1 × 10−3 | 302 ± 11 | 4.6 ± 0.7 |
| Ubc5AE140A | 4.9 ± 0.1 × 10−3 | 174 ± 6 | 4.6 ± 0.6 |
| Ubc5AW141A | 4.7 ± 0.1 × 10−3 | 480 ± 25 | 3.3 ± 0.3 |
| Ubc5AT142A | 1.8 ± 0.1 × 10−3 | 240 ± 2 | 5.2 ± 0.2 |
| Ubc5AQ143A | 4.6 ± 0.1 × 10−3 | 240 ± 10 | 5.1 ± 0.3 |
| Ubc5AK144A | 6.9 ± 0.1 × 10−3 | 190 ± 6 | 4.6 ± 0.6 |
| Ubc5AY145A | NA | NA | NA |
| Ubc5AA146L | 0.10 ± 0.01 × 10−3 | 570 ± 380 | 3.4 ± 1.4 |
| Ubc5AM147A | 4.3 ± 0.1 × 10−3 | 249 ± 6 | 5.7 ± 0.8 |
a Values of kcat determined as Vmax/[E3]o, where [E3]o is calculated from total TRIM protein.
b Values from Table I.
c NA, no activity.