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Updated: Jan 31, 2026

A Protocol for Computer-Based Protein Structure and Function Prediction
Published on: November 3, 2011
Kinetics and Predicted Structure of a Novel Xylose Reductase from Chaetomium thermophilum
Julian Quehenberger1, Tom Reichenbach2, Niklas Baumann3
1Research Division Biochemical Engineering, Institute of Chemical, Environmental and Bioscience Engineering, Faculty of Technical Chemistry, TU Wien, 1060 Vienna, Austria. julian.quehenberger@tuwien.ac.at.
Abstract:
While in search of an enzyme for the conversion of xylose to xylitol at elevated temperatures, a xylose reductase (XR) gene was identified in the genome of the thermophilic fungus Chaetomium thermophilum. The gene was heterologously expressed in Escherichia coli as a His6-tagged fusion protein and characterized for function and structure. The enzyme exhibits dual cofactor specificity for NADPH and NADH and prefers D-xylose over other pentoses and investigated hexoses. A homology model based on a XR from Candida tenuis was generated and the architecture of the cofactor binding site was investigated in detail. Despite the outstanding thermophilicity of its host the enzyme is, however, not thermostable.
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