Ribulose-1,5-bisphosphate
Structural formula | |||||||||||||
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General | |||||||||||||
Surname | Ribulose-1,5-bisphosphate | ||||||||||||
other names |
RubP 2 |
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Molecular formula | C 5 H 12 O 11 P 2 | ||||||||||||
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properties | |||||||||||||
Molar mass | 310.09 g mol −1 | ||||||||||||
Physical state |
firmly |
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safety instructions | |||||||||||||
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As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Ribulose-1,5-bisphosphate (abbreviated RubP 2 ), formerly also called ribulose-1,5-diphosphate , is a sugar molecule ( monosaccharide ) with five carbon atoms to which two phosphate residues are attached. It plays as acceptor for carbon dioxide in the carbon dioxide assimilation in the Calvin cycle a large role in the dark reaction of photosynthesis .
The enzyme that binds CO 2 to ribulose-1,5-bisphosphate is called ribulose-1,5-bisphosphate-carboxylase / oxygenase (RuBisCO) and plays an important role as the starting point for the Calvin cycle. After the CO 2 fixation, the molecule that has become unstable due to the addition of water immediately breaks down into two 3-phosphoglycerate molecules, from which glucose can then be produced after further steps. Ribulose-1,5-bisphosphate is then regenerated from phosphoglycerate.
- Fructose-6-phosphate + 2 glyceraldehyde-3-phosphate + dihydroxyacetone phosphate + 3 ATP 3 ribulose-1,5-bisphosphate + 3 ADP
In order to emphasize that the two phosphate residues are connected to the sugar molecule at different points, the term bisphosphate has become established internationally instead of the previously used diphosphate .
literature
- Jeremy M. Berg, John L. Tymoczko, Lubert Stryer (2007): Biochemistry. Spektrum Akademischer Verlag, 6th edition, ISBN 3-8274-1800-3 .
Individual evidence
- ↑ a b Data sheet D-Ribulose 1,5-bisphosphate sodium salt hydrate from Sigma-Aldrich , accessed on April 22, 2011 ( PDF ).