Download MendeleyStructural Basis for Ligand Binding and Processivity in Cellobiohydrolase Cel6A from Humicola Insolens
Varrot, A., Frandsen, T.P., Von Ossowski, I., Boyer, V., Driguez, H., Schulein, M., Davies, G.J.(2003) Structure 11: 855
- PubMed: 12842048
- DOI: https://doi.org/10.1016/s0969-2126(03)00124-2
- Primary Citation of Related Structures:
1OC5, 1OC6, 1OC7, 1OCB, 1OCJ - PubMed Abstract:
The enzymatic digestion of cellulose entails intimate involvement of cellobiohydrolases, whose characteristic active-center tunnel contributes to a processive degradation of the polysaccharide. The cellobiohydrolase Cel6A displays an active site within a tunnel formed by two extended loops, which are known to open and close in response to ligand binding. Here we present five structures of wild-type and mutant forms of Cel6A from Humicola insolens in complex with nonhydrolyzable thio-oligosaccharides, at resolutions from 1.7-1.1 A, dissecting the structural accommodation of a processing substrate chain through the active center during hydrolysis. Movement of ligand is facilitated by extensive solvent-mediated interactions and through flexibility in the hydrophobic surfaces provided by a sheath of tryptophan residues.
Organizational Affiliation:
Department of Chemistry, University of York, Heslington, Y010 5YW, York, United Kingdom.
