Table 2.
Kinetic Constants of PTPs toward Acidic, Neutral, and Basic Peptide Substrates
| YDEDFpYDYEFa | SASASpYSASAa | YRKRFpYRYKFa | |||||||
|---|---|---|---|---|---|---|---|---|---|
| PTP | kcat (s −1) |
KM (µM) |
kcat/KM x106 (M−1 s−1 ) |
kcat (s−1) |
KM (µM) |
kcat/KM x106 (M−1 s−1 ) |
kcat (s−1) |
KM (µM) |
kcat/KM x106 (M−1 s−1 ) |
| PEST | 470 ± 10 | 2.2 ± 0.5 | 220 | 160 ± 2 | 800 ± 10 | 0.20 | − | − | 0.0015 |
| PTP1B | 21 ± 0.5 | 0.38 ± 0.02 | 55 | 28 ± 0.7 | 12 ± 0.3 | 2.3 | − | − | 0.037 |
| PTPRC | 300 ± 20 | 7.0 ± 0.9 | 43 | 340 ± 50 | 170 ± 20 | 2.0 | − | − | 0.049 |
| PTPRO | 200 ± 10 | 5.7 ± 0.8 | 35 | 240 ± 8 | 250 ± 10 | 0.94 | − | − | 0.053 |
| PTPRB | 55 ± 2 | 1.8 ± 0.4 | 31 | 56 ± 2 | 26 ± 1 | 2.2 | − | − | 0.028 |
| TCPTPb | 9.0 ± 0.4 | 0.31 ± 0.01 | 29 | 17 ± 2 | 10 ± 1 | 1.7 | − | − | 0.032 |
| SHP-1b | 75 ± 2c | 3.2 ± 0.3c | 23c | 26 ± 4c | 2000 ± 400c | 0.013 | − | − | 0.00023 |
| PTPH1 | 2.4 ± 0.06 | 0.28 ± 0.02 | 8.8 | 2.5 ± 0.2 | 5.8 ± 0.7 | 0.44 | − | − | 0.0033 |
| SHP-2b | 43 ± 1c | 6.3 ± 0.4c | 6.8c | 42 ± 5c | 2300 ± 400c | 0.018c | − | − | 0.00015 |
| PTPD2 | 0.073 ± 0.003 | 0.70 ± 0.09 | 0.11 | 0.12 ± 0.006 | 9.4 ± 0.4 | 0.013 | − | − | 0.000082 |
| PTPRA | 19 ± 0.6 | 260 ± 30 | 0.075 | − | − | 0.023 | − | − | 0.045 |
| HePTP | 7.0 ± 0.3 | 280 ± 25 | 0.025 | − | − | 0.00060 | − | − | 0.000010 |
| PTPRD | >0.86 | >60 | 0.014 | − | − | 0.00068 | − | − | 0.00070 |
| PTPD1 | 0.032 ± 0.005 | 26 ± 5 | 0.0012 | − | − | 0.0000038 | − | − | 0.0000057 |
a
All peptides have an N-terminal acetyl group and a C-terminal amide.
b
The peptide WDEDFpYDWEF was used in lieu of YDEDFpYDYEF
c
From ref (10)