Skeletal muscle and brain use a different NADH shuttle, the glycerol 3-phosphate shuttle. It differs from the malate-aspartate shuttle in that it delivers the reducing equivalents from NADH to ubiquinone and thus into complex III, not complex I, providing only enough energy to synthesise 1.5 ATP molecules per pair of electrons.

Summing up the reaction sequence:
Glucose + 38 Pi + 38 ADP + 6O2 → 6CO2 + 38 ATP + 44H2O
Thus, one mole of glucose on complete oxidation to CO2 and H2O in the heart, liver, and kidney, where the malate-aspartate shuttle operates, leads to the production of 38 moles of ATP as shown in Table 8.3.
In skeletal muscles, where glycerol-3-phosphate shuttle operates in which a total of 36 ATP moles is generated when per mole of glucose gets oxidised.
Table 8.3 ATP Yield from Complete Ordination of Glucose
| S.No | Reaction Sequence | ATP/GLUCOSE |
|---|---|---|
| Glycolysis | +2 | |
| 1 | Dephosphorylation of 2 moles of 1,3 DPG | +2 |
| 2 | Dephosphorylation of 2 moles of PEP | |
| 3 | Conversion of pyruvate to acetyl-CoA (2 NADH are formed) | |
| 4 | tCA | |
| 5 | 2 moles of GTP are formed from 2 moles of succinyl CoA | +2 |
| 6 | 6 NADH are formed in oxidation of 2 moles each isocitrate, α-KG and mate. | |
| 7 | 2 FADH2 are formed in oxidation of 2 moles of succinate | |
| 8 | Oxidative phosphorylation | |
| 9 | 2 NADH (glycolysis) 2*3 | +6 |
| 10 | 2 NADH (pyruvate to acetyl-CoA) 2*3 | +6 |
| 11 | 2 FADH (TCA) 2*2 | +4 |
| 12 | 6 NADH (TCA) 6*3 | +18 |
| 13 | 40 − 2 = 38 |
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