Organization of Glucose Metabolism: A Model of Compartments by Poly-Isozymic Complexes
A metabolite being released from the active site of an enzyme may find itself in the predicament of deciding which pathway to choose among several possibilities. For instance, once glucose-6-P has been synthesized several alternative paths are possible, e.g., glycogen synthesis via phosphoglucomutase, glycolysis via phosphoglucose- isomerase, pentose-P pathway via glucose-6-P dehydrogenase, or back again to glucose through glucose-6-phosphatase (Fig. 1). Furthermore, the same situation will happen again at every branch-point along the metabolic maze until a committed step is reached.
KeywordsGlycogen Synthesis Glycogen Phosphorylase Phosphoglucose Isomerase Glucose Incorporation Glycogen Phosphorylase Activity
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