Table 3.
Modeling ATP Production in Wild-Type and CMSII Plants
| ATP/Glc
|
|||||
|---|---|---|---|---|---|
| Glc-O2 | WT-COX | WT-AOX | CMS-COX | CMS-AOX | |
| Glycolysis | 2 ATP/Glc | 2 | 2 | 2 | 2 |
| 2 NADH/Glc | 3 | 1 | 3 | 1 | |
| TCA cycle | 2 ATP/Glc | 2 | 2 | 2 | 2 |
| 2 FADH2/Glc | 3 | 0 | 3 | 0 | |
| 8 NADH/Glc | 18.4 | 6.4 | 12 | 2 | |
| Total | 28.4 | 11.4 | 22 | 7 | |
| ATP/Malate
|
|||||
| Malate-O2 | WT-COX | WT-AOX | CMS-COX | CMS-AOX | |
| Malic enzyme | 1 NADH/mal | 2.3 | 0.8 | 1.5 | 0.25 |
| TCA cycle | 1 ATP/mal | 1 | 1 | 1 | 1 |
| 4 NADH/mal | 9.2 | 3.2 | 6 | 1 | |
| 1 FADH2/mal | 1.5 | 0 | 1.5 | 0 | |
| Total | 14 | 5 | 10 | 2.25 | |
In the top part of the table, ATP/O2 for in vivo respiration was calculated for complete catabolism of glucose (Glc) via AOX and COX pathways separately in wild-type and CMSII plants. Sucrose degradation via invertase gives the same result. Sucrose degradation via PPi-using glycolytic enzymes increases the direct yield of ATP from glycolysis to four per Glc (Browse et al., 2006). The ATP/Glc corresponds to 6 times ATP/O2. In the bottom part of the table, the same calculation is shown for malate, with ATP/malate corresponding to 3 times ATP/O2. Stoichiometries used are described in Methods.