Metabolic Reactions in the HMP Pathway
The hexose monophosphate pathway is responsible for the generation of a substantialfraction of the cytoplasmic NADPH required for biosynthetic reactions, and for thegeneration of ribose-5-phosphate for nucleotide synthesis. Hence, there are the followingtwo phases of HMP pathway:
1) In the oxidation pathway, glucose-6-phosphate is converted to ribulose-5-phosphateby dehydrogenation and decarboxylation reactions.
2) In the nonoxidative phase, ribulose-5-phosphate is converted back to glucose-6-phosphate by a series of reactions involving transketolase and transaldolase.