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Updated: Jun 23, 2026

Dynamic Light Scattering Analysis for the Determination of the Particle Size of Iron-Carbohydrate Complexes
Published on: July 7, 2023
Structural determinants of product specificity of sucrose isomerases
Stéphanie Ravaud1, Xavier Robert, Hildegard Watzlawick
1Institut de Biologie et Chimie des Protéines, UMR 5086-CNRS/Université de Lyon, IFR128 BioSciences Gerland-Lyon Sud, Lyon, France.
Abstract:
The healthy sweetener isomaltulose is industrially produced from the conversion of sucrose by the sucrose isomerase SmuA from Protaminobacter rubrum. Crystal structures of SmuA in native and deoxynojirimycin complexed forms completed with modeling studies unravel the characteristics of the isomaltulose synthases catalytic pocket and their substrate binding mode. Comparison with the trehalulose synthase MutB highlights the role of Arg(298) and Arg(306) active site residues and surface charges in controlling product specificity of sucrose isomerases (isomaltulose versus trehalulose). The results provide a rationale for the specific design of optimized enzymes.
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