1h8v
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THE X-RAY CRYSTAL STRUCTURE OF THE TRICHODERMA REESEI FAMILY 12 ENDOGLUCANASE 3, CEL12A, AT 1.9 A RESOLUTION
OverviewOverview
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 StructureAbout this Structure
1H8V is a Single protein structure of sequence from Hypocrea jecorina with NAG as ligand. Active as Cellulase, with EC number 3.2.1.4 Known structural/functional Sites: , , , , and . Full crystallographic information is available from OCA.
ReferenceReference
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
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