Covalent binding of three epoxyalkyl xylosides to the active site of endo-1,4-xylanase II from Trichoderma reesei.
Havukainen, R., Torronen, A., Laitinen, T., Rouvinen, J.(1996) Biochemistry 35: 9617-9624
- PubMed: 8755744 
- DOI: https://doi.org/10.1021/bi953052n
- Primary Citation of Related Structures:  
1RED, 1REE, 1REF - PubMed Abstract: 
The three-dimensional structures of endo-1,4-xylanase II (XYNII) from Trichoderma reesei complexed with 4,5-epoxypentyl beta-D-xyloside (X-O-C5),3,4-epoxybutyl beta-D-xyloside (X-O-C4), and 2,3-epoxypropyl beta-D-xyloside (X-O-C3) were determined by X-ray crystallography. High-resolution measurement revealed clear electron densities for each ligand. Both X-O-C5 and X-O-C3 were found to form a covalent bond with the putative nucleophile Glu86. Unexpectedly, X-O-C4 was found to bind to the putative acid/base catalyst Glu177. In all three complexes, clear conformational changes were found in XYNII compared to the native structure. These changes were largest in the X-O-C3 complex structure.
Organizational Affiliation: 
Department of Chemistry, University of Joensuu, Finland.