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1h8v
From Proteopedia
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THE X-RAY CRYSTAL STRUCTURE OF THE TRICHODERMA REESEI FAMILY 12 ENDOGLUCANASE 3, CEL12A, AT 1.9 A RESOLUTION
Overview
We present the three-dimensional structure of Trichoderma reesei endoglucanase 3 (Cel12A), a small, 218 amino acid residue (24.5 kDa), neutral pI, glycoside hydrolase family 12 cellulase that lacks a cellulose-binding module. The structure has been determined using X-ray crystallography and refined to 1.9 A resolution. The asymmetric unit consists of six non-crystallographic symmetry-related molecules that were exploited to improve initial multiple isomorphous replacement phasing, and subsequent structure refinement. The enzyme contains one disulfide bridge and is glycosylated at Asp164 by a single N-acetyl glucosamine residue. The protein has the expected fold for a glycoside hydrolase clan-C family 12 enzyme. It contains two beta-sheets, of six and nine strands, packed on top of one another, and one alpha-helix. The concave surface of the nine-stranded beta-sheet forms a large substrate-binding groove in which the active-site residues are located. In the active site, we find a carboxylic acid trio, similar to that of glycoside hydrolase families 7 and 16. The strictly conserved Asp99 hydrogen bonds to the nucleophile, the invariant Glu116. The binding crevice is lined with both aromatic and polar amino acid side-chains which may play a role in substrate binding. The structure of the fungal family 12 enzyme presented here allows a complete structural characterization of the glycoside hydrolase-C clan.
About this Structure
1H8V is a Single protein structure of sequence from Hypocrea jecorina with as ligand. Active as Cellulase, with EC number 3.2.1.4 Known structural/functional Sites: , , , , and . Full crystallographic information is available from OCA.
Reference
The X-ray crystal structure of the Trichoderma reesei family 12 endoglucanase 3, Cel12A, at 1.9 A resolution., Sandgren M, Shaw A, Ropp TH, Wu S, Bott R, Cameron AD, Stahlberg J, Mitchinson C, Jones TA, J Mol Biol. 2001 Apr 27;308(2):295-310. PMID:11327768
Page seeded by OCA on Thu Feb 21 12:58:42 2008
Categories: Cellulase | Hypocrea jecorina | Single protein | Bott, R. | Cameron, A D. | Jones, T A. | Mitchinson, C. | Ropp, T H. | Sandgren, M. | Shaw, A. | Stahlberg, J. | Wu, S. | NAG | Cellulose degradation | Endoglucanase | Gh family 12 | Glycosyl hydrolase | Hydrolase | Trichoderma reesei cel12a
