TABLE 2.
Steady-state kinetic parameters for wild-type Cab and Cab variants with MOPS and imidazole buffers (pH 7.2)
| Variant | Buffer (50 mM) | kcat (104 s−1) | Km in CO2 (mM) | kcat/Km (106 s−1 M−1) |
|---|---|---|---|---|
| Wild type | MOPS | 1.1 ± 0.2 | 2.7 ± 0.2 | 4.1 ± 0.3 |
| Imidazole | 1.3 ± 0.3 | 4.2 ± 0.3 | 3.2 ± 0.4 | |
| D34A | MOPS | 0.11 ± 0.1 | 3.5 ± 0.2 | 2.9 ± 0.2 |
| Imidazole | 0.91 ± 0.05 | 15.3 ± 1.5 | 0.6 ± 0.3 | |
| R36A | MOPS | 0.0024 ± 0.0004 | 35.3 ± 1.7 | 0.00067 ± 0.00003 |
| Imidazole | 0.0030 ± 0.0003 | 47.1 ± 2.2 | 0.00064 ± 0.00006 | |
| D34A-R36A | MOPS | 0.026 ± 0.03 | 9.2 ± 0.3 | 0.029 ± 0.05 |
| Imidazole | 0.15 ± 0.02 | 5.8 ± 0.2 | 0.26 ± 0.08 |