Answer to Question #100982 in Chemistry for Abhishek

Question

How many moles of ATP and NADPH are required to convert 6 moles of CO₂ to fructose-6-phosphate? Give all the reactions involved.

Answer 1

CO₂ is converted to fructose-6-phosphate during the Calvin cycle (the second stage of the photosynthesis process). At the first step, enzyme RuBisCo converts 6 CO₂ molecules into 12 3-phosphoglycerate molecules using 6 ribulose-1,5-diphosphate molecules. 12 ATPs are used during the process. At the next stages, 12 molecules of glyceraldehyde-3-phosphate are produced, whereas 12 NADPH molecules are used in the reaction. Finally, one molecule of fructose-6-phosphate are produced. However, to complete the cycle, 10 molecules of glyceraldehyde-3-phosphate are transformed into 6 ribulose-1,5-diphosphate molecules. 6 ATP molecules are used in the process. As a result, the overall reaction is:

6CO₂ + 18ATP + 12NADPH = fructose-6-phosphate + 18ADP + 12NADP⁺.