Non-cyclic photoreductive carbon fixation in photosynthesis. Light and dark transients of the glycerate-3-P special pair
| Autor: | Karen A. Butcher, Francis K. Fong |
|---|---|
| Rok vydání: | 1988 |
| Předmět: |
Sucrose
Light Ribulose-Bisphosphate Carboxylase Molecular Conformation Biophysics Glyceric Acids Photosynthesis Photochemistry Biochemistry Adduct Ribulosephosphates chemistry.chemical_compound Glyceraldehyde Magnesium Molecular Biology Pentosephosphates Ribulose Carbon fixation Cell Biology Darkness Plants Carbon C3 carbon fixation chemistry Carboxylation |
| Zdroj: | Biochemical and Biophysical Research Communications. 150:399-404 |
| ISSN: | 0006-291X |
| Popis: | It is demonstrated that carbon fixation in photosynthesis is regulated in two kinetically coupled pathways involving the specialized pair of non-equivalent, enzyme-bound glycerate-3-P (3-PGA) molecules obtained from ribulose 1,5-bisphosphate (RuBP) carboxylation in the light.A non-cyclic pathway is suggested (reaction 2) for the direct biosynthesis of sucrose from the 3-PGA obtained from C-3, C-4 and C-5 of the six-carbon carboxylation adduct. Concomitant to the appearance of sucrose as the principal product, the Mg 2+ -bound 3-PGA molecule formed from C-1, C-2 and C-2′ of the C 6 intermediate is released and subsequently reduced in regenerating the RuBP. It is proposed that the nocturnal inhibitor, 2-carboxyarabinitol-1-phosphate (1-PCA) is obtained from a condensation of 3-PGA and glyceraldehyde. |
| Databáze: | OpenAIRE |
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