Presteady State Kinetics of Phosphorothioate Hydrolysis by Alkaline Phosphatase
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چکیده
منابع مشابه
Presteady State Kinetics of Phosphoro - thioate Hydrolysis by Alkaline Phosphatase RATE - LIMITING DEPHOSPHORYLATION
The hydrolysis of 0-p-phenylazophenylphosphorothioate by Escherichia coli alkaline phosphatase was studied by the stopped-flow technique. “Burst” kinetics is observed at both acid and basic pH, suggesting that a step following thiophosphorylation is rate-limiting at all pH values. At pH 8.5, activation of a second active site on the enzyme dimer is observed in the transient phase as subsrrate c...
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The kinetics of ATP binding and hydrolysis (formation of acid-labile phosphate) by the Tetrahymena 30 S dynein ATPase has been measured by chemical quench flow methods. The amplitude of the ATP-binding transient gave a molecular weight per ATP-binding site of approximately 750,000, suggesting nearly 3 ATP binding sites/2 million Mr dynein molecule (Johnson, K. A., and Wall, J.S. (1983) J. Cell ...
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The repressible alkaline phosphatase of Escherichia coli (orthophosphoric monoester phosphohydrolase, EC 3.1.3.1) promises to play a role in biochemical genetics comparable to that played by fl-galactosidase (l-5). It is also being used increasingly for class experiments. The evaluation of the important characteristic kinetic constants for this enzyme, however, poses certain technical difficult...
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Escherichia coli alkaline phosphatase (AP) is the prototypical two metal ion catalyst with two divalent zinc ions bound approximately 4 A apart in the active site. Studies spanning half a century have elucidated many structural and mechanistic features of this enzyme, rendering it an attractive model for investigating the potent catalytic power of bimetallic centers. Unfortunately, fundamental ...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1972
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)44858-8