Ribulose 5-phosphate
Encyclopedia
Ribulose 5-phosphate is one of the end-products of the pentose phosphate pathway
. It is also an intermediate in the Calvin cycle
.
It is formed by phosphogluconate dehydrogenase
, and it can be acted upon by phosphopentose isomerase and phosphopentose epimerase
.
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...
. It is also an intermediate in the Calvin cycle
Calvin cycle
The Calvin cycle or Calvin–Benson-Bassham cycle or reductive pentose phosphate cycle or C3 cycle or CBB cycle is a series of biochemical redox reactions that take place in the stroma of chloroplasts in photosynthetic organisms...
.
It is formed by phosphogluconate dehydrogenase
Phosphogluconate dehydrogenase
Phosphogluconate dehydrogenase is an enzyme in the pentose phosphate pathway. It forms ribulose 5-phosphate from 6-phosphogluconate.It is an oxidative carboxylase that catalyses the decarboxylating reduction of 6-phosphogluconate into ribulose 5-phosphate in the presence of NADP. This reaction is a...
, and it can be acted upon by phosphopentose isomerase and phosphopentose epimerase
Phosphopentose epimerase
Phosphopentose epimerase is an enzyme which intraconverts ribulose 5-phosphate and xylulose 5-phosphate.It plays a role in the Calvin cycle and the pentose phosphate pathway.-External links:* *...
.
See also
- RibuloseRibuloseRibulose is a ketopentose — a monosaccharide containing five carbon atoms, and including a ketone functional group. It has chemical formula 5105. Two enantiomers are possible, D-ribulose and L-ribulose . D-Ribulose is the diastereomer of D-xylulose.Ribulose sugars are composed in the...
- Ribulose-1,5-bisphosphateRibulose-1,5-bisphosphateRibulose-1,5-bisphosphate is an organic substance that is involved in photosynthesis. The anion is a double phosphate ester of the ketose called ribulose. Salts of this species can be isolated, but its crucial biological function involves this colourless anion in solution...