Table 2.
Kinetic properties of UCH37-containing complexes
| Km (μM) | kcat (s−1) | kcat/Km (s−1μM−1) | |
|---|---|---|---|
| UCH37UCHd-228) | 23.4 ± 5.2 | 4.6 ± 0.7 | 0.19 ± 0.05 |
| UCH37 | 20.8 ± 4.4 | 3.9 ± 0.5 | 0.19 ± 0.05 |
| UCH37(M269E, N291D) | n.d. | n.d. | 0.21 ± 0.01 |
| UCH37/RPN13285-407 | 3.1 ± 0.7 | 5.0 ± 0.3 | 1.6 ± 0.4 |
| UCH37(isoform2)/RPN13285-407 | 3.3 ± 0.7 | 4.7 ± 0.3 | 1.4 ± 0.3 |
| UCH37(M148A,F149A)/RPN13285-407 | 21.7 ± 4.7 | 4.7 ± 0.6 | 0.22 ± 0.05 |
| UCH37/RPN13(Q337A,Q338A)285-407 | 7.9 ± 1.2 | 4.7 ± 0.3 | 0.6 ± 0.1 |
| UCH37/NFRKB1-156 | 15.4 ± 2.3 | 0.10 ± 0.01 | 0.006 ± 0.001 |
| UCH37/NFRKB39-156 | 26.5 ± 4.8 | 0.25 ± 0.03 | 0.009 ± 0.002 |
| UCH37/NFRKB1-156f97GSGS100) | 20.3 ± 4.8 | 5.94 ± 0.71 | 0.29 ± 0.08 |
| UCH37/NFRKB1-117 | 29.2 ± 6.0 | 0.15 ± 0.02 | 0.005 ± 0.001 |
Assays were performed with ubiquitin-AMC. Data are reported as best-fit values with standard errors from non-linear regression fit. All UCH37 constructs used for kinetic analysis refer to human isoform 1 unless otherwise noted. n.d. = not determined.