TABLE 3.
Phosphoryl group donor and cation dependence of the ADP-PFK from M. jannaschiia
| Phosphoryl group donor | Divalent cation | Sp act (mU/mg) | Relative activity (%) |
|---|---|---|---|
| ADP | Mg2+ | 8,200 | 100 |
| GDP | Mg2+ | 115 | 1.4 |
| ATP | Mg2+ | 24.6 | 0.3 |
| GTP | Mg2+ | 664 | 8.1 |
| Acetyl-phosphate | Mg2+ | 6,806 | 83 |
| Polyphosphate | Mg2+ | NDb | ND |
| Phosphoenolpyruvate | Mg2+ | ND | ND |
| Pyrophosphate | Mg2+ | ND | ND |
| ADP | Ca2+ | 9,840 | 120 |
| ADP | Co2+ | 6,396 | 78 |
| ADP | Mn2+ | 4,428 | 54 |
| ADP | Zn2+ | ND | ND |
a
Standard enzyme assays were done at 50°C, except that phosphoryl group donors and cations were varied as described in Materials and Methods.
b
ND, not detectable, i.e., the activity was less than 0.3% of the activity under optimal conditions.