This pathway is also called the oxidative pentose pathway and the hexose monophosphate shunt. It has been called the latter because it involves some reactions of the glycolytic pathway and therefore has been viewed as a shunt of glycolysis. It exists in both prokaryotic and eukaryotic cells.
What is a shunt in a metabolic pathway?
The HMP shunt is an alternative pathway to glycolysis and is used to produce ribose-5-phosphate and nicotinamide adenine dinucleotide phosphate (NADPH). This pathway occurs in the oxidative and non-oxidative phases, each comprising a series of reactions.
Why no ATP is formed in HMP shunt?
The HMP consists of two irreversible oxidative reactions and a series of reversible sugar-phosphate conversions. No ATP is consumed or produced directly. Carbon 1 is released from glucose-6-phosphate (G6P) as CO2, and 2 NADPH are produced for each G6P entering the pathway.
