Metabolism of glucose 1,6-P2-III. Partial purification and characterization of glucose 1,6-P2 synthase from pig skeletal muscle

University of Barcelona, Barcino, Catalonia, Spain
Comparative biochemistry and physiology. B, Comparative biochemistry (Impact Factor: 2.07). 02/1988; 90(4):739-44. DOI: 10.1016/0305-0491(88)90328-8
Source: PubMed


1. Glycerate 1,3-P2-dependent glucose, 1,6-P2 synthase has been purified 2000-fold from pig skeletal muscle, with a yield of 75%. 2. The enzyme possesses fructose 1,6-P2-dependent glucose 1,6-P2 synthase and phosphoglucomutase activities, which represent 0.1 and 60% of the main activity, respectively. 3. Both glucose 1-P and glucose 6-P can act as acceptors of the phosphoryl group from glycerate 1,3-P2. 4. The Km values are 19 microM and 67 nM for glucose 1-P and glycerate 1,3-P2, respectively. 5. The enzyme is inhibited by glycerate 2,3-P2, fructose 1,6-P2, glycerate 3-P, phosphoenolpyruvate and lithium, the inhibition pattern varying with the compound.

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