1OCB

Structure of the wild-type cellobiohydrolase Cel6A from Humicolas insolens in complex with a fluorescent substrate

Summary for 1OCB

• Entry DOI: 10.2210/pdb1ocb/pdb
• Related: 1BVW 1GZ1 1HGW 1HGY 1OC5 1OC6 1OC7 1OCJ 1OCN 1QJW 1QK0 1QK2 2BVW
• Descriptor: CELLOBIOHYDROLASE II, 4-amino-4-deoxy-alpha-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-methyl 4-thio-beta-D-glucopyranoside, beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-4)-methyl 4-thio-beta-D-glucopyranoside, ... (7 entities in total)
• Functional Keywords: hydrolase, cellulose degradation, cellobiohydrolase, cellulase, glycoside hydrolase family 6, processive mechanism
• Biological source: HUMICOLA INSOLENS
• Total number of polymer chains: 2
• Total formula weight: 83550.52

Authors

Varrot, A.,Frandsen, T.P.,Von Ossowski, I.,Boyer, V.,Driguez, H.,Schulein, M.,Davies, G.J. (deposition date: 2003-02-07, release date: 2003-07-10, Last modification date: 2023-12-13)

Primary citation

Varrot, A.,Frandsen, T.P.,Von Ossowski, I.,Boyer, V.,Driguez, H.,Schulein, M.,Davies, G.J.
Structural Basis for Ligand Binding and Processivity in Cellobiohydrolase Cel6A from Humicola Insolens
Structure, 11:855-, 2003

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.

PubMed: 12842048
DOI: 10.1016/S0969-2126(03)00124-2

Experimental method

X-RAY DIFFRACTION (1.75 Å)