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PDBsum entry 1e0x
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* Residue conservation analysis
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References listed in PDB file
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Key reference
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Title
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Substrate specificity in glycoside hydrolase family 10. Structural and kinetic analysis of the streptomyces lividans xylanase 10a.
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Authors
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V.Ducros,
S.J.Charnock,
U.Derewenda,
Z.S.Derewenda,
Z.Dauter,
C.Dupont,
F.Shareck,
R.Morosoli,
D.Kluepfel,
G.J.Davies.
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Ref.
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J Biol Chem, 2000,
275,
23020-23026.
[DOI no: ]
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PubMed id
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Abstract
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Endoxylanases are a group of enzymes that hydrolyze the beta-1, 4-linked xylose
backbone of xylans. They are predominantly found in two discrete sequence
families known as glycoside hydrolase families 10 and 11. The Streptomyces
lividans xylanase Xyl10A is a family 10 enzyme, the native structure of which
has previously been determined by x-ray crystallography at a 2.6 A resolution
(Derewenda, U., Swenson, L., Green, R., Wei, Y., Morosoli, R., Shareck, F.,
Kluepfel, D., and Derewenda, Z. S. (1994) J. Biol. Chem. 269, 20811-20814).
Here, we report the native structure of Xyl10A refined at a resolution of 1.2 A,
which reveals many features such as the rare occurrence of a discretely
disordered disulfide bond between residues Cys-168 and Cys-201. In order to
investigate substrate binding and specificity in glycoside hydrolase family 10,
the covalent xylobiosyl enzyme and the covalent cellobiosyl enzyme intermediates
of Xyl10A were trapped through the use of appropriate 2-fluoroglycosides. The
alpha-linked intermediate with the nucleophile, Glu-236, is in a (4)C(1) chair
conformation as previously observed in the family 10 enzyme Cex from
Cellulomonas fimi (Notenboom, V., Birsan, C., Warren, R. A. J., Withers, S. G.,
and Rose, D. R. (1998) Biochemistry 37, 4751-4758). The different interactions
of Xyl10A with the xylobiosyl and cellobiosyl moieties, notably conformational
changes in the -2 and -1 subsites, together with the observed kinetics on a
range of aryl glycosides, shed new light on substrate specificity in glycoside
hydrolase family 10.
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Figure 4.
Fig. 4. Double displacement reaction mechanism as applied
to the S. lividans Xyl10A.
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Figure 6.
Fig. 6. Schematic diagram of the protein-ligand
interactions for the 2F-xylobiosyl enzyme intermediate of
Xyl10A. Distances less than 3.2 Å are indicated.
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The above figures are
reprinted
by permission from the ASBMB:
J Biol Chem
(2000,
275,
23020-23026)
copyright 2000.
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Secondary reference #1
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Title
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Crystal structure, At 2.6-A resolution, Of the streptomyces lividans xylanase a, A member of the f family of beta-1,4-D-Glycanases.
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Authors
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U.Derewenda,
L.Swenson,
R.Green,
Y.Wei,
R.Morosoli,
F.Shareck,
D.Kluepfel,
Z.S.Derewenda.
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Ref.
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J Biol Chem, 1994,
269,
20811-20814.
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PubMed id
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Secondary reference #2
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Title
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Crystal structure, At 2.6-A resolution, Of the streptomyces lividans xylanase a, A member of the f family of beta-1,4-D-Glycanases.
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Authors
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U.Derewenda,
L.Swenson,
R.Green,
Y.Wei,
R.Morosoli,
F.Shareck,
D.Kluepfel,
Z.S.Derewenda.
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Ref.
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J Biol Chem, 1994,
269,
20811-20814.
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PubMed id
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