Question

How many ATP are produced from 6 glucose molecules that pass through the PPP and then are metabolized to pyruvate through glycolysis? Compare this with the number of ATP produced from 6 glucose molecules that go through glycolysis without the PPP.

Answer 1

ATP produced from 1 glucose molecule without going thhrough PPP is 30 or 32

Therefore, 6 glucose molecules produce 180 or 192 ATP

A glucose enters PPP as Glucose-6-phospate to yield ribulose 5 phosphate and carbon dioxide.

6G-6-P + 12 NADP+----------> 6 Ribulose-5-Phosphate + 6 CO2 + 12 NADPH

6 Ribulose-5-Phosphate -------> 4 G-6-P + 2 Glyceraldehyde 3-phosphate

2 glyceraldehyde 3-Phosphate enter glycoslysis and produces 2 NADH, 4ATP,

In total G-6-P produces 12 NADPH, 2 NADH, 4 ATP

1 NADPH/NADH is equivalent to 2.5 ATP, therefore, 35+4= 39 ATP