Question

Calculate the cost, in ATP equivalents, of converting 12 acetyl-CoA to lignocerate(a ${\mathbf{\text{C}}}_{\mathbf{\text{24}}}$fatty acid; Table 9-1) when elongation occurs in the mitochondrion

Short answer

The cost of converting 12 acetyl-CoA to lignocerate, in ATP equivalents, when elongation occurs in the mitochondrion, is a total of $62$ ATP consumed

Step-by-step solution

Definition of Palmitate

Palmitate is a C16 saturated fatty acid that requires a total of 7 rounds of -oxidation to yield 8 acetyl-CoA molecules.Acetyl-CoA is then transferred to be used in the citric acid cycle to yield a sufficient amount of ATP.

ATP in palmitate synthesis

Palmitate synthesis consumes a total of 7 A T P and 14NADPH (1NADPH = 2.5ATP, which is equivalent to $\left(\text{14×2.5}\right)$ ATP = 35ATP).

ATP in lignocerate synthesis in mitochondria

When 4 more 2-carbon units as acetyl-CoA in the mitochondria are added to palmitate to produce lignocerate, this consumes a total of:

1., which is equivalent to $\text{(4×2.5)ATP=10ATP)}$

2.which is equivalent to $\text{(4×2.5)ATP=10ATP).}$

Therefore, this would give a total of $\text{(7+35+10+10)ATP=62ATP}$consumed.