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The stereochemical course of yeast hexokinase-catalysed phosphoryl transfer by using adenosine 5'[gamma(S)-16O,17O,18O]triphosphate as substrate.

ABSTRACT: Adenosine 5'[gamma(S)-16O, 17O, 18O]triphosphate has been synthesized and used to determine the stereochemical course of phosphoryl transfer catalysed by yeast hexokinase. The chirality at phosphorus of the D-glucose 6-[16O,17O,18O]phosphate formed was analysed, after cyclization and methylation, by 31P n.m.r. spectroscopy. The phosphoryl transfer was found to occur with inversion of configuration, with a stereoselectivity in excess of 94%. The simplest interpretation of this result is that the phosphoryl group is transferred between substrates in the enzyme-substrate ternary complex by an 'in line' mechanism.

SUBMITTER: Lowe G

PROVIDER: S-EPMC1163354 | biostudies-other | 1981 Oct

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.

Project description:Bacillus stearothermophilus and rabbit skeletal-muscle phosphofructokinases catalyse the transfer of the chiral [16O,17O,18O]phosphoryl group from D-fructose 1[(S)-16O,17O,18O],6-bisphosphate to ADP with inversion of configuration at the phosphorus atom. D-Fructose 1[(S)-16O,17O,18O],-bisphosphate was synthesized in situ from sn-glycerol 3[(S)-16O,17O,18O]phosphate. The simplest interpretation of these results is that the phosphoryl group is transferred between substrates in the enzyme substrate ternary complexes by an 'in-line' mechanism.

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The stereochemical course of phosphoryl transfer catalysed by glucokinase.

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| S-EPMC1163660 | biostudies-other

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

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| S-EPMC1163426 | biostudies-other

The stereochemical course of phosphoryl transfer catalysed by glucose 6-phosphatase.

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The stereochemical course of phosphoryl transfer catalysed by polynucleotide kinase (bacteriophage-T4-infected Escherichia coli B).

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The stereochemical course of hydrolysis catalysed by snake venom 5'-nucleotide phosphodiesterase.

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The stereochemical course of reactions catalysed by the cellobiohydrolases produced by Talaromyces emersonii.

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The stereochemical course of sulphuryl transfer catalysed by arylsulphatase II from Aspergillus oryzae.

Project description:Phenyl [(R)-16O,17O,18O]sulphate was synthesized and used to study the stereochemical course of sulphuryl transfer to p-cresol catalysed by arylsulphatase II from Aspergillus oryzae. The reaction was shown to proceed with retention of configuration at the sulphur atom, providing evidence for the involvement of a sulpho-enzyme intermediate on the reaction pathway.

| S-EPMC1133079 | biostudies-other

Stable isotope compositions (?2H, ?18O and ?17O) of rainfall and snowfall in the central United States.

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| S-EPMC5928101 | biostudies-literature

The mechanism of the reaction catalysed by adenosine triphosphate-creatine phosphotransferase.

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