Mechanism of Ribulose-Diphosphate Carboxydismutase Reaction
Ribulose-1,5-P 2 labelled with tritium in the C-3 position was converted to 2 moles of phosphoglyceric acid by the carboxydismutase. Over 98 % of the radioactivity was found in the water, less than 0.1 % being in phosphoglyceric acid, indicating that the proton lost from the 3 position of the substrate does not contribute to the formation of product. The tritiated substrate reacts at only 20 % the rate of the normal carrier species. Neither substrate nor product show significant proton exchange with the medium due to the enzyme.
KeywordsIsotope Effect Pyruvate Kinase Tritiated Water Glycerol Kinase Glyceric Acid
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- 1.Müllhofer, G., and Rose, I. A., J. Biol. Chem. 240 (1965) 1341.Google Scholar
- 2.Calvin, M., J. Chem. Soc. (1956) 1895.Google Scholar
- 4.Simon, H., Dorrer, H. D., and Trebst, A., Z. Naturforsch. 19b (1964) 734.Google Scholar
- 12.Hurwitz, J., In Methods in Enzymology (edited by S. P. Colowick and O. Kaplan ), Academic Press, New York 1956, Vol. V, p. 258.Google Scholar
- 13.Racker, E., In Methods in Enzymology (edited by S. P. Colowick and O. Kaplan ), Academic Press, New York 1956, Vol. V, p. 266.Google Scholar