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A stereochemical investigation of phosphoryl transfer catalysed by phosphoglucomutase by the use of alpha-D-glucose 1-[(S)-16O,17O,18O]phosphate.

ABSTRACT: Rabbit muscle phosphoglucomutase converts alpha-D-glucose 1-[(S)-16O,17O,18O]phosphate into D-glucose 6-[16O,17O,18O]phosphate, 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.

SUBMITTER: Lowe G

PROVIDER: S-EPMC1163426 | biostudies-other | 1981 Dec

REPOSITORIES: biostudies-other

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The stereochemical course of phosphoryl transfer catalysed by Bacillus stearothermophilus and rabbit skeletal-muscle phosphofructokinase with a chiral [16O,17O,18O]phosphate ester.

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