Table I.
Regulation of GAPN activity by MgCl2, adenine nucleotides, and PPi
The state compounds were included in the assay medium at 3 mm concentration, without or with further addition of 5 mm MgCl2. Values are means of four independent experiments made by triplicate.
| Compound
|
GAPN Activity
|
|||
|---|---|---|---|---|
| Endosperm
|
Leaf
|
|||
| −Mg2+ | +Mg2+ | −Mg2+ | +Mg2+ | |
| milliunits mg−1 | ||||
| None | 120 ± 6.0 | 330 ± 16.1 | 450 ± 20.1 | 400 ± 25.9 |
| AMP | 110 ± 5.5 | 200 ± 10.2 | 380 ± 19.5 | 360 ± 22.2 |
| ADP | 110 ± 5.0 | 210 ± 10.1 | 320 ± 20.8 | 330 ± 17.6 |
| ATP | 81 ± 3.2 | 330 ± 18.3 | 350 ± 21.4 | 300 ± 17.5 |
| PPi | 84 ± 3.7 | 340 ± 15.0 | 430 ± 25.0 | 410 ± 23.3 |