Question

assume that for each C=C double bond in a fatty acid, 1 FAD is not needed and therefore 1 FADH is not produced in beta-oxidation of a fatty acid.

What is the ATP yield for the catabolism of archidonyl-CoA. This compound has a 4 C=C double bonds in the fatty acyl chain
a. 130 ATP per arachindonyl-CoA
b. 134 ATP per arachindonyl-CoA
c. 132 ATP per arachindonyl-CoA
d. 126 ATP per arachindonyl-CoA

Answer 1

Answer: number of carbons in given fatty acid = 20

Moles of acetyl-CoA formed = 10

1 mol of ATP is split into AMP and 2 Pi -2 ATP
10 mol of acetyl-CoA formed (10x10 ATP) 100 ATP
5 mol of FADH2 formed (5x1.5 ATP) 7.5 ATP
9 mol of NADH formed (9x2.5 ATP) 22.5 ATP

Total 128 ATP

Since, the question is only asking for the ATP yeild in catabolism of arachindonyl-CoA.

Therefore, the total ATP yeild is 130 ATP

So, the correct option is (a) 130 ATP per arachindonyl-CoA

{ For each double bond, no FADH2 is formed, there number of moles of FADH2 is taken as 9-4 = 5}