Table I.
The activity of marker enzymes for different organelles and cellular compartments during the isolation of intact small amyloplasts from potato tubers
| Compartment and Enzyme | Tuber Tissue | Crude Extract | Small Amyloplasts | |
|---|---|---|---|---|
| nmol min−1 g−1 fresh wt | nmol min−1 tuber−1 | |||
| Amyloplast | ||||
| AGPase | 1116 | 27,900 | 3200 (100) | 11.7 (0.37) |
| PPasea | 520 | 13,000 | 1800 (100) | 5.0 (0.28) |
| Cytosol | ||||
| ADH | 274 | 6,850 | 1870 (100) | 0.8 (0.04) |
| PFPb | 816 | 20,400 | 2550 (100) | 0.9 (0.04) |
| Vacuole | ||||
| α-Mannosidase | 62 | 1,560 | 88 (100) | 0.0 (0.00) |
| Mitochondria | ||||
| Cyt c oxidase | 550 | 13,800 | 1500 (100) | 3.0 (0.20) |
The yield (in parentheses) is presented as the percentage of the enzymatic activity in the tuber tissue and was calculated for each separate marker enzyme. The data presented are results from one typical set of experiments.
a
PPase, Alkaline inorganic pyrophosphatase.
b
PFP, Pyrophosphate: Fru-6-P phosphotransferase.