Hexose Monophosphate

Hexose Monophosphate Pentose Phosphate Pathway Glycolysis, TCA, and oxidative phosphorylation are primarily concerned with the generation of ATP. The PPP meets the need of all organisms for a source of NADPH to use in reductive biosynthesis. The reducing power is NADPH. There is a fundamental distinction NADH  NADPH  The direction of HMP depends on the supply and demand for intermediates in the cycle…

Two Major Functions NADPH Ribose Overall reaction: 3G-6-P + 6NADP+  3CO2 + 2G-6-P + Glyceraldehyde-3P + 6NADPH + 6H+ It occurs in the cytosol because NADP+ is used as a hydrogen acceptor. There are two sequential reactions. Oxidative Nonoxidative

Oxidative and Nonoxidative Reactions In oxidative, G-6-P undergoes dehydrogenation and decarboxylation to give a pentose ribulose-5-P. In nonoxidative, ribulose 5-P is converted back to G-6-P by a series of reactions involving two enzymes Transketolase Transaldolase Dehydrogenation of G-6-P is the major biological control of the HMP. G-6-PD is strongly inhibited by NADPH.

Oxidative Branch