title: Inhibition of a protein tyrosine phosphatase using mesoporous oxides.
abstract: The feasibility of utilizing mesoporous matrices of alumina and silica for the inhibition of enzymatic activity is presented here. These studies were performed on a protein tyrosine phosphatase by the name chick retinal tyrosine phosphotase-2 (CRYP-2), a protein that is identical in sequence to the human glomerular epithelial protein-1 and involved in hepatic carcinoma. The inhibition of CRYP-2 is of tremendous therapeutic importance. Inhibition of catalytic activity was examined using the sustained delivery of p-nitrocatechol sulfate (pNCS) from bare and amine functionalized mesoporous silica (MCM-48) and mesoporous alumina (Al(2)O(3)). Among the various mesoporous matrices employed, amine functionalized MCM-48 exhibited the best release of pNCS and also inhibition of CRYP-2. The maximum speed of reaction v(max) (=160 +/- 10 micromol/mnt/mg) and inhibition constant K(i) (=85.0 +/- 5.0 micromol) estimated using a competitive inhibition model were found to be very similar to inhibition activities of protein tyrosine phosphatases using other methods.
authors.affiliation: Solid State and Structural Chemistry Unit, and Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India.
authors.forename: S
authors.initials: S
authors.lastname: Kapoor
authors.forename: T S
authors.initials: TS
authors.lastname: Girish
authors.forename: S S
authors.initials: SS
authors.lastname: Mandal
authors.forename: B
authors.initials: B
authors.lastname: Gopal
authors.forename: A J
authors.initials: AJ
authors.lastname: Bhattacharyya
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D002645:Chickens; D018360:Crystallography, X-Ray; D004791:Enzyme Inhibitors / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D010087:Oxides / Q000737:chemistry*; D016062:Porosity; D017434:Protein Structure, Tertiary; D017027:Protein Tyrosine Phosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D054631:Receptor-Like Protein Tyrosine Phosphatases, Class 3 / Q000737:chemistry / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012822:Silicon Dioxide / Q000737:chemistry / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D010087:Oxides; D011994:Recombinant Proteins; D012822:Silicon Dioxide; D017027:Protein Tyrosine Phosphatases; D054631:Receptor-Like Protein Tyrosine Phosphatases, Class 3; D000537:Aluminum Oxide