A stereochemical investigation of phosphoryl transfer catalysed by phosphoglucomutase by the use of a - D - glucose 1 - [ ( S ) - 60 , 170 , 180 jphosphate
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چکیده
Rabbit muscle phosphoglucomutase converts a-D-glucose 1_[(S)-160,17O,8Olphosphate into D-glucose 6-[160,'70,18Olphosphate, which is shown by 31P n.m.r. spectroscopy, after cyclization and methylation, to have the (S)-configuration at the phosphorus atom. Since phosphoglucomutase is known to catalyse phosphoryl transfer by way of a phospho-enzyme intermediate, and since individual phosphoryl-transfer steps appear in general to occur with inversion of configuration, this observation is most simply interpreted in terms of a double-displacement mechanism with two phosphoryl-transfer steps.
منابع مشابه
The stereochemical course of phosphoryl transfer catalysed by glucose 6-phosphatase.
Rat liver microsomal glucose 6-phosphatase catalyses phosphoryl transfer between D-glucose 6-[(R)-16O,17O,18O]phosphate and D-glucose with retention of configuration at the phosphorus atom. Since individual phosphoryl-transfer steps appear in general to occur with inversion of configuration, this observation is most simply interpreted in terms of a double-displacement mechanism with a phosphory...
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