Ribose 5-phosphate is both a product and an intermediate of the pentose phosphate pathway

Pentose phosphate pathway

The pentose phosphate pathway is a process that generates NADPH and pentoses . There are two distinct phases in the pathway. The first is the oxidative phase, in which NADPH is generated, and the second is the non-oxidative synthesis of 5-carbon sugars...

. The last step of the oxidative reactions in the pentose phosphate pathway is the production of ribulose-5-phosphate. Depending on the body's state, ribulose-5-phosphate can reversibly isomerize to ribose-5-phosphate. Ribulose-5-phosphate can alternatively undergo a series of isomerizations as well as transaldolations and transketolations that result in the production of other pentoses phosphates as well as fructose 6-phosphate

Fructose 6-phosphate

Fructose 6-phosphate is fructose sugar phosphorylated on carbon 6 . The β-D-form of this compound is very common in cells. The vast majority of glucose and fructose entering a cell will become converted to this at some point...

 and glyceraldehyde-3-phosphate (both intermediates in glycolysis

Glycolysis

Glycolysis is the metabolic pathway that converts glucose C6H12O6, into pyruvate, CH3COCOO− + H+...

).

The enzyme ribose-phosphate diphosphokinase

Ribose-phosphate diphosphokinase

Ribose-phosphate diphosphokinase is an enzyme that converts ribose 5-phosphate into phosphoribosyl pyrophosphate.It is classified under .-External Links:* * * * *...

 converts ribose-5-phosphate into phosphoribosyl pyrophosphate

Phosphoribosyl pyrophosphate

Phosphoribosyl pyrophosphate is a pentosephosphate.It is formed from ribose 5-phosphate by the enzyme ribose-phosphate diphosphokinase.It plays a role in transferring phospho-ribose groups in several reactions:...

.