Ribulose-1,5-diphosphate carboxylase

All enzymes exhibit various features that could conceivably be elements in the regulation of their activity in cells. All have a characteristic pH optimum which makes it possible for their catalytic rates to be altered by changes in intracellular pH (e.g. in ribulose diphosphate carboxylase(l7>). The activities also depend on the concentration of substrates, which may vary according to intracellular conditions. Moreover, many require metal ions or vitamins, and the activity of enzymes may be a function of the concentrations in which such materials are present (e.g. the effect of iron limitation on the citric acid fermentation of Aspergillus niger ). However, over and above these factors, some enzymes have other properties that... 

I. Storroe, and B. R. McFadden, Ribulose diphosphate carboxylase/oxygenase in toluene-permeabilized Rhodospirillum rubrum, Biochem. J. 1983, 212, 45-54. 

Ribulose diphosphate carboxylase Succinic dehydrogenase Superoxide dismutase Tyrosine aminotransferase Xanthine dehydrogenase Xanthine oxidase... 

Deoxyribonucleic acid Nicotiana syivestris clone NySS4 ribulose diphosphate carboxylase small subunit gene) 950b, 1919a, 4249... 

Multi-Enzyme Cofactor Requiring Processes - A more complex level of applied enzymology is reached in the use of multi-enzyme schemes to synthesize complex molecules. Examples of such syntheses include ribu-lose-1,5-diphosphate, important in the study of ribulose-diphosphate carboxylase lactosamine,from the first use of the Lelolr pathway enzjnnes in synthesis and S-adenosyl-L-methionine. ... 

Bowes, G., W. L. Ogren, and R. H. Hageman Phosphoglycolate Production Catalyzed by Ribulose Diphosphate Carboxylase. Biochem. Biophys. Res. Commun. 45, 716 (1971). 

The most important CO2 activation process is photosynthesis, in which solar photons drive a reaction that would otherwise be uphill thermodynamically the reduction of CO2 to carbohydrates coupled to water oxidation to O2. Many metalloenzymes are involved in these processes, the one that fixes CO2 is ribulose diphosphate carboxylase, in which an enolate anion of the sugar nucleophilically attacks the CO2 carbon. Cu(II), Mn(II), and are all present in the active enzyme, and one of these probably plays a role in polarizing the CO2, perhaps via an tj -OCO complex. 

Bahr,J.T., Jensen,R.G. Ribulose diphosphate carboxylase from freshly ruptured spinach chloroplasts having an in vivo K (C02). Plant Physiol. 53, 39 14 (1974)... 

Cooper,T.G., Filmer,0., Wischnick,M., Lane,M.D. The active species of CO2 utilized by ribulose diphosphate carboxylase. J. Biol. Chem. 244,1081 (1969)... 

A. RIBULOSE DIPHOSPHATE CARBOXYLASE AND THE PENTOSE PHOSPHATE CYCLE... 

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