Table 2.
Properties of Petunia BSMTs
| Enzyme | Holoenzyme Mass by Gel Filtration (D) |
Subunit Mass by SDS-PAGE (D) |
Calculated Subunit Mass (D) |
Substrate | pH Optimum |
Apparent Km for Substrate (μM) |
kcat × 10−2 (s−1) | kcat/Km (mM−1·s−1) |
|---|---|---|---|---|---|---|---|---|
| BSMT1 | 78,430 | ∼45,000 | 40,659 | SAM SA | 1.93 ± 0.18 | 1.45 ± 0.024 | 7.65 ± 0.618 | |
| SAM BA | 15.78 ± 1.34 | 0.75 ± 0.023 | 0.48 ± 0.047 | |||||
| Salicylic acid | 7.0 to 8.0 | 51.55 ± 2.73 | 1.2 ± 0.16 | 0.23 ± 0.038 | ||||
| Benzoic acid | 7.5 | 1273.2 ± 37 | 0.39 ± 0.04 | 0.003 ± 0.0003 | ||||
| BSMT2 | 77,100 | ∼45,000 | 40,673 | SAM SA | 2.76 ± 0.04 | 0.57 ± 0.099 | 2.07 ± 0.015 | |
| SAM BA | 30.78 + 0.78 | 0.79 ± 0.06 | 0.26 ± 0.015 | |||||
| Salicylic acid | 7.0 to 7.5 | 69.6 ± 1.31 | 0.4 ± 0.028 | 0.057 ± 0.005 | ||||
| Benzoic acid | 6.5 to 7.5 | 2355.9 ± 88 | 0.32 ± 0.0096 | 0.0014 ± 0.0084 |