adenosine-5--o-(3-thiotriphosphate) and 5-diphosphomevalonic-acid
adenosine-5--o-(3-thiotriphosphate) has been researched along with 5-diphosphomevalonic-acid* in 2 studies
Other Studies
2 other study(ies) available for adenosine-5--o-(3-thiotriphosphate) and 5-diphosphomevalonic-acid
Article | Year |
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Mevalonate-5-diphosphate decarboxylase: stereochemical course of ATP-dependent phosphorylation of mevalonate 5-diphosphate.
Chicken liver mevalonate-5-diphosphate decarboxylase catalyzes the reaction of mevalonate 5-diphosphate (MVADP) with ATP to produce isopentenyl diphosphate, ADP, CO2, and inorganic phosphate. The overall reaction involves an anti elimination of the tertiary hydroxyl and carboxyl groups. To investigate the mechanism for transfer of the terminal phosphoryl group of ATP to the C-3 oxygen of MVADP, we have carried out the reaction using stereospecifically labeled (Sp)-adenosine 5'-O-(3-thio[3-17O2,18O]triphosphate) [( gamma-17O2,18O]ATP gamma S) in place of ATP. The configuration of the [17O,18O]thiophosphate produced was found to be Rp, corresponding to overall inversion of configuration at phosphorus in the thiophosphoryl group transfer step. This result is consistent with the direct transfer of the thiophosphoryl group from (Sp)-[gamma-17O2,18O]ATP gamma S to MVADP at the active site. Our result does not indicate the involvement of a covalent thiophosphoryl-enzyme on the reaction pathway. Topics: Adenosine Triphosphate; Animals; Binding Sites; Carboxy-Lyases; Chickens; Kinetics; Liver; Magnetic Resonance Spectroscopy; Mass Spectrometry; Mevalonic Acid; Oxygen Isotopes; Phosphorylation | 1986 |
The interaction of phosphorothioate analogues of ATP with phosphomevalonate kinase. Kinetic and 31P NMR studies.
The diastereomers of adenosine 5'-O-(1-thiotriphosphate) (ATP alpha S), adenosine 5'-O-(2-thiotriphosphate) (ATP beta S), and adenosine 5'-O-(3-thiotriphosphate) (ATP gamma S) could act as substrates for phosphomevalonate kinase in the presence of Mg2+ and Cd2+ as activating divalent metal cations. The Sp diastereomer of ATP alpha S was the preferred substrate regardless of the metal ion used, consistent with the metal ion not binding to the alpha-phosphate. With ATP beta S, the Sp diastereomer was the preferred substrate with Mg2+, and the Rp diastereomer was the preferred substrate with Cd2+. The reversal of specificity establishes that the metal is chelated through the beta-phosphate in the active site of the phosphomevalonate kinase reaction. A comparison of the Vmax values as a function of substitution of oxygen by sulfur showed the order for Mg2+ to be: ATP greater than ATP alpha S(Sp) greater than ATP alpha S(Rp) greater than ATP beta S(Sp) greater than ATP gamma S greater than ATP beta S(Rp). With Cd2+ as the activating metal ion, the order was: ATP greater than ATP alpha S(Sp) greater than ATP alpha S(Rp) greater than ATP beta S(Rp) greater than ATP gamma S greater than ATP beta S(Sp). It is concluded that the chelate structure of metal ATP substrate in the phosphomevalonate kinase reaction is the delta, beta, gamma-bidentate complex. 31P NMR measurements and radioassay with [2-14C] phosphomevalonate were used to measure the equilibrium of the reaction catalyzed by phosphomevalonate kinase with ATP and phosphorothioate analogues of ATP as the phosphoryl group donor. The order as a phosphate donor as determined by both methods in the phosphomevalonate kinase reaction is ATP beta S greater than ATP alpha S greater than ATP greater than ATP gamma S. Except for ATP gamma S, the equilibrium is shifted in the direction of formation of ADP alpha S and ADP beta S relative to ADP formation. Thus, ATP beta S rather than ATP would be effective for the synthesis of diphosphomevalonate. The phosphomevalonate kinase reaction could also be used to synthesize mevalonate 5-(2-thiodiphosphate) using ATP gamma S as the phosphoryl group donor. Topics: Adenosine Diphosphate; Adenosine Triphosphate; Animals; Cadmium; Isomerism; Kinetics; Liver; Magnesium; Magnetic Resonance Spectroscopy; Mevalonic Acid; Phosphotransferases; Phosphotransferases (Phosphate Group Acceptor); Substrate Specificity; Swine; Thionucleotides | 1985 |