In: Biology
Compare the metabolic pathways of lactate and alanine by drawing out the associated degradation pathway from lactate/alanine to CO2 & H2O. Calculate the number of moles of ATP formed from complete oxidation of 1 mol of each of these molecules. Why is the ATP yield different between the two?
Lactate will convert into pyruvate which leads to production of one NADH. Now pyruvate under go acetyl coA fprmation with release of one NADH. While acetyl CoA undergo to CAC cycle to produce 3 NADH, 1FADH2, and 1 ATP. So total 4 NADH and 1 FADH2 undergo Electron Transport Chain to form ATP. So net ATP production-
1) 4 NADH produce 4x2.5= 10 ATP
2) 1 FADH2 produced 1x1.5= 1.5 ATP
3) 1 ATP
So total ATP produced from complete oxidation of lactate is 10+1.5+1= 12.5 ATP
While alanine will for pyruvate with release of amine group. Pyruvate undergo now same pathways as for lactate to produce similar way ATP .
Here final ATP will be less as there is no NADH produced during conversion of alanine to pyruvate which was produced during lactase to pyruvate conversion. So 2.5 ATP less produced during alanine oxidation.
So final ATP produced during oxidation of alanine will be 10ATP.
Hope it's clear..thanks