TABLE 2.
FadD33 wild type and FadD33-K260A mutant acyl chain length selectivity and kinetic parameters
Initial velocities were measured spectrophotometrically in 100 mm HEPES, pH 7.8, 10 mm MgCl2, and 250 mm NaCl as described under “Materials and Methods.”
| Enzyme/Substrate | Km | kcat | kcat/Km |
|---|---|---|---|
| μm | min−1 | μm−1 min−1 | |
| FadD33 wild type | |||
| Hexanoic acid (C6) | 129 ± 25 | 0.11 ± 0.01 | 0.0008 ± 0.0001 |
| Decanoic acid (C10) | 121 ± 22 | 1.5 ± 0.1 | 0.012 ± 0.004 |
| Lauric acid (C12) | 21 ± 4 | 2.4 ± 0.1 | 0.110 ± 0.003 |
| Palmitic acid (C16) | 1.9 ± 0.3 | 4.2 ± 0.1 | 2.3 ± 0.1 |
| ATP | 15 ± 1 | 1.3 ± 0.2 | 0.085 ± 0.008 |
| MbtL-holo | 106 ± 19 | 2.0 ± 0.1 | 0.018 ± 0.006 |
| FadD33-K260A | |||
| Lauric acid (C12) | 3.4 ± 0.5 | 0.51 ± 0.01 | 0.15 ± 0.01 |