Structural highlights
Function
GUX_CELFI Hydrolyzes both cellulose and xylan. Has also weak endoglucanase activity. The biological conversion of cellulose to glucose generally requires three types of hydrolytic enzymes: (1) Endoglucanases which cut internal beta-1,4-glucosidic bonds; (2) Exocellobiohydrolases that cut the dissaccharide cellobiose from the non-reducing end of the cellulose polymer chain; (3) Beta-1,4-glucosidases which hydrolyze the cellobiose and other short cello-oligosaccharides to glucose.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The three-dimensional structure of a catalytically competent glycosyl-enzyme intermediate of a retaining beta-1,4-glycanase has been determined at a resolution of 1.8 A by X-ray diffraction. A fluorinated slow substrate forms an alpha-D-glycopyranosyl linkage to one of the two invariant carboxylates, Glu 233, as supported in solution by 19F-NMR studies. The resulting ester linkage is coplanar with the cyclic oxygen of the proximal saccharide and is inferred to form a strong hydrogen bond with the 2-hydroxyl of that saccharide unit in natural substrates. The active-site architecture of this covalent intermediate gives insights into both the classical double-displacement catalytic mechanism and the basis for the enzyme's specificity.
Crystallographic observation of a covalent catalytic intermediate in a beta-glycosidase.,White A, Tull D, Johns K, Withers SG, Rose DR Nat Struct Biol. 1996 Feb;3(2):149-54. PMID:8564541[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ White A, Tull D, Johns K, Withers SG, Rose DR. Crystallographic observation of a covalent catalytic intermediate in a beta-glycosidase. Nat Struct Biol. 1996 Feb;3(2):149-54. PMID:8564541