title: myo-inositol 1,4,5-trisphosphorothioate is a potent competitive inhibitor of human erythrocyte 5-phosphatase.
abstract: The effect of the myo-inositol 1,4,5-trisphosphate (IP3) analogue, myo-inositol 1,4,5-trisphosphorothioate (IPS3) on the dephosphorylation of D-5-[32P]IP3 by the 5-phosphatase from human erythrocyte membranes has been investigated. DL-IPS3 was found to act as a competitive inhibitor with a Ki of 6 microM, making it the most potent inhibitor currently available for this enzyme. L-IP3 inhibited the enzyme with a Ki of 124 microM and was more potent than D-2,3-diphosphoglycerate (Ki 978 microM).
authors.affiliation: Department of Chemistry, University of Leicester, England.
authors.forename: A M
authors.initials: AM
authors.lastname: Cooke
authors.forename: S R
authors.initials: SR
authors.lastname: Nahorski
authors.forename: B V
authors.initials: BV
authors.lastname: Potter
mesh_terms: D004912:Erythrocytes / Q000201:enzymology; D006801:Humans; D066298:In Vitro Techniques; D007294:Inositol / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D015544:Inositol 1,4,5-Trisphosphate / Q000031:analogs & derivatives; D000072181:Inositol Polyphosphate 5-Phosphatases; D007700:Kinetics; D009946:Organothiophosphorus Compounds / Q000378:metabolism* / Q000494:pharmacology; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors*
chemical_list: D009946:Organothiophosphorus Compounds; C054737:inositol 1,4,5-triphosphorothioate; D007294:Inositol; D015544:Inositol 1,4,5-Trisphosphate; D010744:Phosphoric Monoester Hydrolases; D000072181:Inositol Polyphosphate 5-Phosphatases