CRYSTALLOGRAPHY AND MUTAGENESIS OF TRANSKETOLASE - MECHANISTIC IMPLICATIONS FOR ENZYMATIC THIAMIN CATALYSIS

The ThDP dependent enzyme transketolase is a convenient model system t o study enzymatic thiamin catalysis. Crystallographic studies of the e nzyme have identified the ThDP binding fold, the V-conformation of ThD P as the relevant conformation in enzymatic catalysis and details of e nzyme-substrate interactions. Based on this structural information, th e function of various active site residues in substrate binding and ca talysis has been probed by site-directed mutagenesis. (C) 1998 Elsevie r Science B.V. All rights reserved.