Kinetic parameters of the wild-type and R510Q mutant erythrocyte pyruvate kinases in the presence of allosteric effectors
| . | PEP* . | FBP† . | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1.5 mM ATP FBP (−) . | 1.5 mM ATP 30 μM FBP . | ATP (−) . | 1.5 mM ATP . | |||||||||||
| kcat(s−1) . | S0.5 (mM) . | nH . | kcat/S0.5(s−1/mM) . | kcat (s−1) . | S0.5 (mM) . | nH . | kcat/S0.5(s−1/mM) . | kcat (s−1) . | S0.5 (μM) . | nH . | kcat (s−1) . | S0.5 (μM) . | nH . | |
| Wild-type | 349 ± 7 | 1.96 ± 0.15 | 2.09 ± 0.11 | 178 | 350 ± 10 | 0.42 ± 0.02 | 1.17 ± 0.11 | 833 | 64.9 ± 5 | 3.4 ± 0.02 | 1.56 ± 0.09 | 64.9 ± 5 | 6.7 ± 0.02 | 1.81 ± 0.09 |
| R510Q | 330 ± 8 | 3.92 ± 0.35 | 1.99 ± 0.14 | 84.2 | 305 ± 10 | 0.95 ± 0.05 | 2.02 ± 0.13 | 321 | 35.9 ± 6 | 0.5 ± 0.01 | 1.01 ± 0.11 | 14.4 ± 6 | 0.8 ± 0.01 | 1.10 ± 0.11 |
| . | PEP* . | FBP† . | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1.5 mM ATP FBP (−) . | 1.5 mM ATP 30 μM FBP . | ATP (−) . | 1.5 mM ATP . | |||||||||||
| kcat(s−1) . | S0.5 (mM) . | nH . | kcat/S0.5(s−1/mM) . | kcat (s−1) . | S0.5 (mM) . | nH . | kcat/S0.5(s−1/mM) . | kcat (s−1) . | S0.5 (μM) . | nH . | kcat (s−1) . | S0.5 (μM) . | nH . | |
| Wild-type | 349 ± 7 | 1.96 ± 0.15 | 2.09 ± 0.11 | 178 | 350 ± 10 | 0.42 ± 0.02 | 1.17 ± 0.11 | 833 | 64.9 ± 5 | 3.4 ± 0.02 | 1.56 ± 0.09 | 64.9 ± 5 | 6.7 ± 0.02 | 1.81 ± 0.09 |
| R510Q | 330 ± 8 | 3.92 ± 0.35 | 1.99 ± 0.14 | 84.2 | 305 ± 10 | 0.95 ± 0.05 | 2.02 ± 0.13 | 321 | 35.9 ± 6 | 0.5 ± 0.01 | 1.01 ± 0.11 | 14.4 ± 6 | 0.8 ± 0.01 | 1.10 ± 0.11 |
Results are means (SE) for 3 determinations from 4 different protein preparations. PEP, phosphoenolpyruvate; FBP, fructose 1,6-bisphosphate; ATP, adenosine triphosphate.
Kinetic parameters were obtained at fixed 1.5 mM ADP by fitting data to the Hill plot.
Kinetic parameters were obtained at fixed 0.1 mM PEP and 1.5 mM ADP by fitting data to the Hill plot.