TABLE 1.
Properties of the crotonyl-CoA hydratase homologs in M. sedula, based on the published datae
| Substrate, parameter | Msed_2001a,b | Msed_0399c,d | Msed_0336c | Msed_0384c | Msed_0385c | Msed_0566c |
|---|---|---|---|---|---|---|
| 3-Hydroxypropionyl-CoA | ||||||
| Vmax, U mg−1 protein | 372a/544b | 4.8 | 4 (Sp. act.) | 4 (Sp. act.) | ND | ND |
| Km, mM | 0.06a/0.025b | 0.06 | ND | ND | ||
| kcat/Km, s−1 mM−1 | 3,190a/10,260b | 94 | NA | NA | ||
| Crotonyl-CoA | ||||||
| Vmax, U mg−1 protein | ND | 526 | 52 | 454 | ND | ND |
| Km, mM | 0.97 | 0.08 | 0.22 | |||
| kcat/Km, s−1 mM−1 | 640 | 317 | 1,043 | |||
| (S)-3-Hydroxybutyryl-CoA | ||||||
| Vmax, U mg−1 protein | 385a | 246 | 119 | 242 | ND | ND |
| Km, mM | 0.075a | 0.86 | 0.07 | 0.05 | ||
| kcat/Km, s−1 mM−1 | 2,640a | 338 | 830 | 2,445 | ||
| Presence in all autotrophic Sulfolobalesc | Yes | No | No | No | No | Yes |
a
The protein was purified from M. sedula cell extracts and characterized as 3-hydroxypropionyl-CoA hydratase; data from reference 15.
b
Data from reference 18
c
Data from reference 17.
d
Bifunctional crotonyl-CoA hydratase/3-hydroxybutyryl-CoA dehydrogenase Msed_0399 is a fusion protein consisting of an enoyl-CoA hydratase domain and a dehydrogenase domain.
e
The Vmax values were extrapolated to 75°C based on the assumption that a 10°C rise in temperature doubles the reaction rate. ND, not determined; NA, not applicable.