Table 1.
Steady-State Kinetic Properties of SRPK1 Mutantsa
| Protein | kcat (s−1) | KATP (μM) | kcat/KATP (M−1s−1 ×10−3) | KSR (nM) | kcat/KSR (M−1s−1×10−5) | Ki,ADP (μM) |
|---|---|---|---|---|---|---|
| SRPK1 | 1.0 (.05) | 11 (1.8) | 91 (16) | 120 (16) | 83 (12) | 10 (1) |
| SRPK1(ΔS) | 0.07 (0.01) | 14 (1) | 5.0 (.4) | 140 (20) | 5.0 (.8) | 13 (1) |
| SRPK1(ΔN) | 0.1 (008) | 20 (3) | 5.0 (.48) | 440 (100) | 2.3 (.6) | 13 (3) |
| SRPKI(ΔSINT) | 1.0 (.04) | 50 (7) | 20 (3) | 190 (30) | 53 (9) | 54 (7) |
| SRPKI(ΔSαi) | 0.20 (.01) | 30 (7) | 6.7 (1.5) | 90 (20) | 22 (5) | 18 (5) |
| SRPK1(ΔSα2) | 0.90 (.06) | 16 (2) | 56 (9) | 130 (20) | 69 (14) | |
| SRPK1(I228G) | 1.1 (.05) | 24 (7) | 46 (14) | 70 (18) | 160 (41) | |
| SRPK1(I228K) | 0.8 (.07) | 90 (13) | 8.8 (1.5) | 240 (90) | 33 (13) | |
| SRPK1(ΔNNT) | 1.0 (.05) | 25 (2) | 40 (4) | 38 (6) | 260 (43) | |
| SRPK1(ΔNCT) | 0.4 (.04) | 36 (8) | 11 (3) | 410 (50) | 9.1 (1.4) | |
| SRPK1(ΔNSα1) | 0.10 (.01) | 12 (2) | 8.3 (1.4) | 340 (78) | 2.9 (.72) |
a
Numbers in parentheses next to data represent standard deviations on each fit.