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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.

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The stereochemical course of phosphoryl transfer catalysed by glucokinase.

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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 sulphuryl transfer catalysed by arylsulphatase II from Aspergillus oryzae.

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

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