Studying non-covalent enzyme carbohydrate interactions by STD NMR.
Saturation transfer difference NMR spectroscopy is used to study non-covalent interactions between four different glycostructure transforming enzymes and selected substrates and products. Resulting binding patterns represent a molecular basis of specific binding between ligands and biocatalysts. Substrate and product binding to Aspergillus fumigatus glycosidase and to Candida tenuis xylose reductase are determined under binding-only conditions. Measurement of STD effects in substrates and products over the course of enzymatic conversion provides additional information about ligand binding during reaction. Influences of co-substrates and co-enzymes in substrate binding are determined for Schizophyllum commune trehalose phosphorylase and C. tenuis xylose reductase, respectively. Differences between ligand binding to wild type enzyme and a corresponding mutant enzyme are shown for Corynebacterium callunae starch phosphorylase and its His-334-->Gly mutant. The resulting binding patterns are discussed with respect to the possibility that ligands do not only bind in the productive mode.
Brecker
Lothar
L
University of Vienna, Institute of Organic Chemistry, Währinger Strasse 38, A-1090 Wien, Austria. lothar.brecker@univie.ac.at
Schwarz
Alexandra
A
Goedl
Christiane
C
Kratzer
Regina
R
Tyl
Catrin E
CE
Nidetzky
Bernd
B
D000449:Aldehyde Reductase / Q000737:chemistry / Q000378:metabolism*; D001232:Aspergillus fumigatus / Q000201:enzymology; D002175:Candida / Q000201:enzymology; D050260:Carbohydrate Metabolism; D003352:Corynebacterium / Q000201:enzymology; D005964:Glucosyltransferases / Q000737:chemistry / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism*; D008024:Ligands; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D017354:Point Mutation; D012567:Schizophyllum / Q000201:enzymology; D024941:Starch Phosphorylase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001617:beta-Glucosidase / Q000378:metabolism
D008024:Ligands; D000449:Aldehyde Reductase; D005964:Glucosyltransferases; D024941:Starch Phosphorylase; C023181:alpha,alpha-trehalose phosphorylase; D006026:Glycoside Hydrolases; D001617:beta-Glucosidase