TABLE 1.
Lactate
|
C2-d-Lactate
|
|||||||
---|---|---|---|---|---|---|---|---|
Rate constants | 23.1°C | 32.5°C | ΔG‡, kcal/mol | ΔH, kcal/mol | 23.0°C | 32.5°C | ΔG‡, kcal/mol | ΔH, kcal/mol |
k1, M−1s−1 | 5.8 × 106 | 6.19 × 106 | 1.2 | 0.9 | 5.8 × 106 | 6.19 × 106 | 1.2 | 0.9 |
k−1, s−1 | 500 | 559 | 2.1 | 500 | 559 | 2.1 | ||
k2, M−1s−1 | 3.00 × 107 | 3.043 × 107 | 0.27 | 1.7 | 3.00 × 107 | 3.043 × 107 | 0.27 | 1.7 |
k−2, s−1 | 1.05 × 105 | 1.17 × 105 | 2.0 | 1.05 × 105 | 1.17 × 105 | 2.0 | ||
k3, s−1 | 430 | 940 | 14.8 | −0.18 | 410 | 860 | 13.9 | 0.24 |
k−3, s−1 | 217 | 470 | 14.7 | 200 | 425 | 14.1 | ||
k4, s−1 | 700 | 1350 | 12.5 | 1.60 | 372 | 880 | 16.2 | 1.44 |
k−4, s−1 | 637 | 1337 | 14.1 | 343 | 876 | 17.6 | ||
k5, s−1 | 240 | 210 | −2.5 | 5.1 | 355 | 350 | −0.3 | 3.3 |
k−5, s−1 | 520 | 595 | 2.6 | 755 | 888 | 3.0 | ||
k6, s−1 | 750 | 1750 | 16.1 | 10.4 | 545 | 1430 | 18.1 | 8.4 |
k−6, M−1s−1 | 1.48 × 107 | 2.01 × 107 | 5.7 | 1.16 × 107 | 1.95 × 107 | 9.7 | ||
k7, s−1 | 32 | 90 | 19.4 | 9.5 | 32 | 90 | 19.4 | 9.5 |
k−7, M−1s−1 | 3.3 × 107 | 5.6 × 107 | 9.9 | 3.3 × 107 | 5.6 × 107 | 9.9 |
The reaction system: 0.46 mN LDH, 0.5 mM NAD+, and 5 mM lactate or C2-deuterated lactate. Fitting results are shown in bold; all other values are initial approximations. The number of significant digits does not represent precision of the absolute values. The errors evaluated from the spread of values through the number of nearly successful simulations are: k3, ±40%; k−3 and k−6, ±30%; k4 and k−4, ±20%; k5 and k−5, ±50%; and k6, ±15%.