1NAE
Structure of CsCBM6-3 from Clostridium stercorarium in complex with xylotriose
Summary for 1NAE
Entry DOI | 10.2210/pdb1nae/pdb |
Related PRD ID | PRD_900117 |
Descriptor | putative xylanase, beta-D-xylopyranose-(1-4)-beta-D-xylopyranose-(1-4)-beta-D-xylopyranose, CALCIUM ION, ... (4 entities in total) |
Functional Keywords | carbohydrate-binding module, beta-sandwich, xylan, xylooligosaccharide, hydrolase |
Biological source | Clostridium stercorarium |
Total number of polymer chains | 1 |
Total formula weight | 17860.39 |
Authors | Boraston, A.B.,Notenboom, V.,Warren, R.A.J.,Kilburn, D.G.,Rose, D.R.,Davies, G. (deposition date: 2002-11-27, release date: 2003-03-18, Last modification date: 2023-08-16) |
Primary citation | Boraston, A.B.,Notenboom, V.,Warren, R.A.J.,Kilburn, D.G.,Rose, D.R.,Davies, G. Structure and ligand binding of carbohydrate-binding module CsCBM6-3 reveals similarities with fucose-specific lectins and "galactose-binding" domains J.Mol.Biol., 327:659-669, 2003 Cited by PubMed Abstract: Carbohydrate-binding polypeptides, including carbohydrate-binding modules (CBMs) from polysaccharidases, and lectins, are widespread in nature. Whilst CBMs are classically considered distinct from lectins, in that they are found appended to polysaccharide-degrading enzymes, this distinction is blurring. The crystal structure of CsCBM6-3, a "sequence-family 6" CBM in a xylanase from Clostridium stercorarium, at 2.3 A reveals a similar, all beta-sheet fold to that from MvX56, a module found in a family 33 glycoside hydrolase sialidase from Micromonospora viridifaciens, and the lectin AAA from Anguilla anguilla. Sequence analysis leads to the classification of MvX56 and AAA into a family distinct from that containing CsCBM6-3. Whilst these polypeptides are similar in structure they have quite different carbohydrate-binding specificities. AAA is known to bind fucose; CsCBM6-3 binds cellulose, xylan and other beta-glucans. Here we demonstrate that MvX56 binds galactose, lactose and sialic acid. Crystal structures of CsCBM6-3 in complex with xylotriose, cellobiose, and laminaribiose, 2.0 A, 1.35 A, and 1.0 A resolution, respectively, reveal that the binding site of CsCBM6-3 resides on the same polypeptide face as for MvX56 and AAA. Subtle differences in the ligand-binding surface give rise to the different specificities and biological activities, further blurring the distinction between classical lectins and CBMs. PubMed: 12634060DOI: 10.1016/S0022-2836(03)00152-9 PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (2.05 Å) |
Structure validation
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