1wd3
From Proteopedia
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| , resolution 1.75Å | |||||||
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| Ligands: | |||||||
| Activity: | Alpha-N-arabinofuranosidase, with EC number 3.2.1.55 | ||||||
| Related: | 1WD4
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of arabinofuranosidase
Overview
As the first known structures of a glycoside hydrolase family 54 (GH54) enzyme, we determined the crystal structures of free and arabinose-complex forms of Aspergillus kawachii IFO4308 alpha-l-arabinofuranosidase (AkAbfB). AkAbfB comprises two domains: a catalytic domain and an arabinose-binding domain (ABD). The catalytic domain has a beta-sandwich fold similar to those of clan-B glycoside hydrolases. ABD has a beta-trefoil fold similar to that of carbohydrate-binding module (CBM) family 13. However, ABD shows a number of characteristics distinctive from those of CBM family 13, suggesting that it could be classified into a new CBM family. In the arabinose-complex structure, one of three arabinofuranose molecules is bound to the catalytic domain through many interactions. Interestingly, a disulfide bond formed between two adjacent cysteine residues recognized the arabinofuranose molecule in the active site. From the location of this arabinofuranose and the results of a mutational study, the nucleophile and acid/base residues were determined to be Glu(221) and Asp(297), respectively. The other two arabinofuranose molecules are bound to ABD. The O-1 atoms of the two arabinofuranose molecules bound at ABD are both pointed toward the solvent, indicating that these sites can both accommodate an arabinofuranose side-chain moiety linked to decorated arabinoxylans.
About this Structure
1WD3 is a Single protein structure of sequence from Aspergillus kawachii. Full crystallographic information is available from OCA.
Reference
Crystal structure of a family 54 alpha-L-arabinofuranosidase reveals a novel carbohydrate-binding module that can bind arabinose., Miyanaga A, Koseki T, Matsuzawa H, Wakagi T, Shoun H, Fushinobu S, J Biol Chem. 2004 Oct 22;279(43):44907-14. Epub 2004 Aug 3. PMID:15292273
Page seeded by OCA on Mon Mar 31 00:34:37 2008
