cancer therapy. Sigrid Eggera, Apirat ... a Institute of Biotechnology and Biochemical Engineering, ... of Oxford, Botnar Research Centre, Oxford OX3 7LD,.
P003 Human UDP-glucose dehydrogenase: The potential
of structural and molecular enzymology as tools for cancer therapy Sigrid Eggera, Apirat Chaikuadb, Kathryn L Kavanaghb, Udo Oppermannb, and Bernd Nidetzkya a Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, Petersgasse 12/1, A - 8010 Graz, Austria b Structural Genomics Consortium, University of Oxford, Botnar Research Centre, Oxford OX3 7LD, United Kingdom
UDP-glucose dehydrogenase (UGDH (EC1.1.1.22)) catalyzes in two successive NAD+ dependent oxidations the conversion of UDP-glucose to yield UDP-glucuronic acid combining an alcohol and aldehyde dehydrogenase activity in one catalytic centre. In mammals, the product serves as precursor for biosynthesis of glycosaminoglycans like heparin, hyaluronic acid and chondroitin sulphate (1). Elevated levels of hyaluronan have been strongly implicated in epithelial tumor progression and inhibition of hyaluronan synthesis has been reported to restrict in vivo tumor growth (1). Furthermore, UGDH was recently proposed as novel biomarker for prostate cancer (2). Therefore the enzyme is a potential target for specific inhibitor design and elucidation of the complex mechanism and detailed knowledge of structure-function relationships provide the tools for rational design of compounds. In this work structural and mechanistic analysis were combined to portray the reaction coordinate of UGDH. Protein structures provide snapshots at crucial steps including the trapped intermediate and thus unique insights along the reaction coordinate. Transient kinetic analysis, proton transfer studies and structureguided site directed mutagenesis dissect the successive oxidation steps and reveal the challenging reaction mechanism. 1. Simpson, M. A. et al. (2002) Am. J. Pathol. 161(3), 849-857 2. Huang, D., et al. (2010) 3rd. International journal of cancer 126(2), 315-327
