1hn0
From Proteopedia
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CRYSTAL STRUCTURE OF CHONDROITIN ABC LYASE I FROM PROTEUS VULGARIS AT 1.9 ANGSTROMS RESOLUTION
Overview
Chondroitin Sulfate ABC lyase I from Proteus vulgaris is an endolytic, broad-specificity glycosaminoglycan lyase, which degrades chondroitin, chondroitin-4-sulfate, dermatan sulfate, chondroitin-6-sulfate, and, hyaluronan by beta-elimination of 1,4-hexosaminidic bond to unsaturated, disaccharides and tetrasaccharides. Its structure revealed three domains., The N-terminal domain has a fold similar to that of carbohydrate-binding, domains of xylanases and some lectins, the middle and C-terminal domains, are similar to the structures of the two-domain chondroitin lyase AC and, bacterial hyaluronidases. Although the middle domain shows a very low, level of sequence identity with the catalytic domains of chondroitinase AC, and hyaluronidase, the residues implicated in catalysis of the latter, enzymes are present in chondroitinase ABC I. The substrate-binding site in, chondroitinase ABC I is in a wide-open cleft, consistent with the, endolytic action pattern of this enzyme. The tryptophan residues crucial, for substrate binding in chondroitinase AC and hyaluronidases are lacking, in chondroitinase ABC I. The structure of chondroitinase ABC I provides a, framework for probing specific functions of active-site residues for, understanding the remarkably broad specificity of this enzyme and perhaps, engineering a desired specificity. The electron density map showed clearly, that the deposited DNA sequence for residues 495-530 of chondroitin ABC, lyase I, the segment containing two putative active-site residues, contains a frame-shift error resulting in an incorrectly translated amino, acid sequence.
About this Structure
1HN0 is a Single protein structure of sequence from Proteus vulgaris with NA as ligand. Active as Chondroitin-sulfate-ABC endolyase, with EC number 4.2.2.20 Full crystallographic information is available from OCA.
Reference
Crystal structure of Proteus vulgaris chondroitin sulfate ABC lyase I at 1.9A resolution., Huang W, Lunin VV, Li Y, Suzuki S, Sugiura N, Miyazono H, Cygler M, J Mol Biol. 2003 May 2;328(3):623-34. PMID:12706721
Page seeded by OCA on Tue Nov 20 16:39:48 2007
