tailieunhanh - Báo cáo khoa học: Pathways and products for the metabolism of vitamin D3 by cytochrome P450scc

Whether dimerization is a general regulatory mechanism of receptor protein-tyrosine phosphatases (RPTPs) is a subject of debate. Biochemical evidence demonstrates that RPTPaand cluster of differentiation (CD)45 dimerize. | ỊFEBS Journal Pathways and products for the metabolism of vitamin D3 by cytochrome P450scc Robert C. Tuckey1 Wei Li2 z Jordan K. Zjawiony3 z Michal A. Zmijewski4 z Minh N. Nguyen1 Trevor Sweatman5 Duane Miller2 and Andrzej Slominski4 1 Schoolof Biomolecular Biomedicaland ChemicalSciences The University of Western Australia Crawley Australia 2 Department of PharmaceuticalSciences College of Pharmacy University of Tennessee Health Science Center Memphis TN USA 3 Department of Pharmacognosy and NationalCenter for NaturalProducts Research Research Institute of PharmaceuticalSciences School of Pharmacy University of Mississippi University MS USA 4 Department of Pathology and Laboratory Medicine and the Center for Cancer Research University of Tennessee Health Science Center Memphis TN USA 5 Department of Pharmacology and the Center for Cancer Research University of Tennessee Health Science Center Memphis TN USA Keywords CYP11A1 cytochrome P450scc hydroxyvitamin D3 NMR vitamin D3 Correspondence R. C. Tuckey Schoolof Biomolecular Biomedical and Chemical Sciences M310 The University of Western Australia Crawley WA 6009 Australia Fax 61 8648 81148 Tel 61 8648 83040 E-mail rtuckey@ These authors contributed equally to this work Received 11 February 2008 revised 14 March 2008 accepted 17 March 2008 doi Cytochrome P450SCC CYP11A1 can hydroxylate vitamin D3 to produce 20-hydroxyvitamin D3 and other poorly characterized hydroxylated productS. The preSent Study aimed to identify all the productS of vitamin D3 metaboliSm by P450Scc aS well aS the pathwayS leading to their formation. BeSideS 20-hydroxyvitamin D3 other major metaboliteS of vitamin D3 were a dihydroxyvitamin D3 and a trihydroxyvitamin D3 product. The dihydroxyvitamin D3 was clearly identified as 20 23-dihydroxyvitamin D3 by NMR in contraSt to previouS reportS that poStulated hydroxyl groupS in positions 20 and 22. NMR of the trihydroxy product identified it as 17a 20