Table 2.
Kinetic parameters for the wild-type, D144N and D144A sn-glycerol-1-phosphate dehydrogenases (Gro1PDH) in dihydroxyacetone phosphate (DHAP) reduction with NADPH as the coenzyme. These parameters were estimated with the Marquardt-Levenberg method (Menke 1989, Press et al. 1992) in experiments in which a fixed concentration of substrate or coenzyme and appropriate ranges of concentrations of the other reactant were used. Abbreviations: kcat = turnover number; Ka = Km for NADPH; Kb = Km for DHAP; and Kia = dissociation constant for NADPH.
| Kinetic parameter | Wild type | D144N | D144A |
| kcat (min–1) | 90.42 ± 3.01 | 284.1 ± 50.8 | 210.4 ± 7.91 |
| Ka (mM) | 0.086 ± 0.01 | 0.165 ± 0.06 | 0.039 ± 0.006 |
| Kb (mM) | 0.050 ± 0.02 | 0.360 ± 0.03 | 0.218 ± 0.030 |
| Kia (mM) | 0.257 ± 0.02 | 0.022 ± 0.01 | 0.013 ± 0.002 |
| % Fit | 99.8 | 99.7 | 99.7 |
| SD | 0.06 | 0.19 | 0.18 |