| Popis: |
The properties of the reaction between ribose 1-phosphate and glucose 1,6-diphosphate as catalyzed by crystalline phosphoglucomutase have been studied with a spectrophotometrical assay, which can be used for a specific quantitative determination of glucose 1,6-diphosphate. It was found that the rate of the reaction depends on the sequence of addition of some of the components. The reaction required both cysteine and magnesium ions. High concentrations of magnesium ions were inhibitory, whereas no such effect was found for high cysteine concentrations. The stoichiometry of the reactions catalyzed by phosphoglucomutase in the presence of ribose 1-phosphate and glucose 1,6-diphosphate has been worked out, and the optimum conditions for formation of ribose 1,5-diphosphate have been determined. Under the conditions used here also deoxyribose 1-phosphate, galactose 1-phosphate, and ribose 5-phosphate react with glucose 1,6-diphosphate. |
