Table 2.
Enzyme capacity of CBB and TCA cycles at midday.
| Enzyme | Source | Enzyme Activity (nmol min−1 mg−1 Protein) | |||
|---|---|---|---|---|---|
| WT | OE7 | P2TOM4 | P2TOC1 | ||
| FBA | Chloroplast | 154 ± 0.6 | 180 ± 6.6 * | 134 ± 4.8 * | 158 ± 3.8 |
| NADP+-GAPDH | Chloroplast | 164 ± 5.6 | 176 ± 3.3 * | 148 ± 4.5 * | 183 ± 1.8 * |
| NADP+-MDH | Chloroplast | 474 ± 4.5 | 552 ± 24 * | 482 ± 37 | 584 ± 27 * |
| NAD+-MDH | Leaf | 3273 ± 51 | 3289 ± 26 | 3790 ± 58 * | 3511 ± 36 * |
| NAD+-MDH | Mitochondria | 17,244 ± 130 | 18,144 ± 350 * | 17,950 ± 80 * | 17,455 ± 490 |
| NAD+-ME | Mitochondria | 137 ± 1.0 | 151 ± 1.7 * | 162 ± 1.1* | 149 ± 1.6 * |
| Citrate synthase | Mitochondria | 5.4 ± 0.6 | 5.3 ± 0.9 | 5.5 ± 0.4 | 5.3 ± 0.0 |
| Aconitase | Mitochondria | 80.0 ± 4.6 | 79.1 ± 3.4 | 113.4 ± 1.7* | 99.4 ± 0.3 * |
| NAD+-ICDH | Mitochondria | 65.8 ± 1.7 | 84.8 ± 3.7 * | 86.4 ± 1.4* | 69.3 ± 0.9 * |
| NADP+-ICDH | Leaf | 59.8 ± 1.7 | 41.3 ± 0.5 * | 62.8 ± 1.7 | 61.9 ± 0.8 |
| 2OGDH | Mitochondria | 18.1 ± 0.3 | 20.9 ± 0.5 * | 19.5 ± 0.2* | 18.3 ± 0.1 * |
| SDH | Mitochondria | 63.1 ± 5.3 | 96.3 ± 8.0 * | 76.4 ± 2.3* | 83.0 ± 0.81 * |
| Fumarase | Mitochondria | 440 ± 11 | 404 ± 15 * | 441 ± 19 | 390 ± 12 * |
Data are means ± SD of 3–4 biological replicates. Independent sample t-test was carried out. Significant differences between WT and either OE7, P2TOM4, or P2TOC1 are shown by asterisks. * p < 0.05, n ≥ 3. FBA, fructose bisphosphate aldolase; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; ICDH, isocitrate dehydrogenase; MDH, malate dehydrogenase; ME, malic enzyme; 2OGDH, 2-oxoglutarate dehydrogenase; SDH, succinate dehydrogenase.