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PDBsum entry 6cel
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References listed in PDB file
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Key reference
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Title
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High-Resolution crystal structures reveal how a cellulose chain is bound in the 50 a long tunnel of cellobiohydrolase i from trichoderma reesei.
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Authors
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C.Divne,
J.Ståhlberg,
T.T.Teeri,
T.A.Jones.
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Ref.
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J Mol Biol, 1998,
275,
309-325.
[DOI no: ]
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PubMed id
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Note In the PDB file this reference is
annotated as "TO BE PUBLISHED".
The citation details given above were identified by an automated
search of PubMed on title and author
names, giving a
percentage match of
96%.
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Abstract
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Detailed information has been obtained, by means of protein X-ray
crystallography, on how a cellulose chain is bound in the cellulose-binding
tunnel of cellobiohydrolase I (CBHI), the major cellulase in the hydrolysis of
native, crystalline cellulose by the fungus Trichoderma reesei. Three
high-resolution crystal structures of different catalytically deficient mutants
of CBHI in complex with cellotetraose, cellopentaose and cellohexaose have been
refined at 1.9, 1.7 and 1.9 A resolution, respectively. The observed binding of
cellooligomers in the tunnel allowed unambiguous identification of ten
well-defined subsites for glucosyl units that span a length of approximately 50
A. All bound oligomers have the same directionality and orientation, and the
positions of the glucosyl units in each binding site agree remarkably well
between the different complexes. The binding mode observed here corresponds to
that expected during productive binding of a cellulose chain. The structures
support the hypothesis that hydrolysis by CBHI proceeds from the reducing
towards the non-reducing end of a cellulose chain, and they provide a structural
explanation for the observed distribution of initial hydrolysis products.
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Figure 1.
Figure 1. Schematic representation of the CBHI catalytic
domain with a cellooligomer bound in sites −7 to +2.
Secondary-structure elements are coloured as follows: β
strands, blue arrows; α helices, red spirals; loop regions,
yellow coils. The cellooligomer is shown in pink as a
ball-and-stick object. The illustration was created with
MOLSCRIPT (Kraulis, 1991).
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Figure 5.
Figure 5. Tryptophan residues from T. reesei CBHI (yellow)
and CBHII (red) aligned with respect to a single glucose
residue. Tryptophan-indole rings interacting with the more
hydrophobic β face a shown “above” the glucosyl unit, and
those interacting with the α face “below”.
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The above figures are
reprinted
by permission from Elsevier:
J Mol Biol
(1998,
275,
309-325)
copyright 1998.
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Secondary reference #1
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Title
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Activity studies and crystal structures of catalytically deficient mutants of cellobiohydrolase i from trichoderma reesei.
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Authors
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J.Ståhlberg,
C.Divne,
A.Koivula,
K.Piens,
M.Claeyssens,
T.T.Teeri,
T.A.Jones.
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Ref.
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J Mol Biol, 1996,
264,
337-349.
[DOI no: ]
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PubMed id
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Figure 2.
Figure 2. Close-up view of a superposition of the CBHI
wild-type and mutant active sites: wild-type/IBTG
(beige), E212Q (blue), D214N (magenta) and E212Q/cel-
lobiose (green). Only the residues close to the cleavage
site are shown. For clarity, the ligands and water
molecules have been omitted. The residue types given
refer to those of wild-type CBHI. In the D214N model, a
calcium ion is bound to Glu212. The side-chain of Gln175
flips to participate in metal co-ordination. The illustration
was created using the program O (Jones et al., 1991).
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Figure 5.
Figure 5. Superposition of residues in the active site of
CBHI (beige) and the Bacillus macerans 1,3-1,4-b-glu-
canase (blue; PDB accession code 1MAC). The side-chains
are presented as ball-and-stick models.
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The above figures are
reproduced from the cited reference
with permission from Elsevier
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Secondary reference #2
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Title
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The three-Dimensional crystal structure of the catalytic core of cellobiohydrolase i from trichoderma reesei.
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Authors
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C.Divne,
J.Ståhlberg,
T.Reinikainen,
L.Ruohonen,
G.Pettersson,
J.K.Knowles,
T.T.Teeri,
T.A.Jones.
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Ref.
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Science, 1994,
265,
524-528.
[DOI no: ]
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PubMed id
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Secondary reference #3
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Title
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Crystallization and preliminary X-Ray studies on the core proteins of cellobiohydrolase i and endoglucanase i from trichoderma reesei.
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Authors
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C.Divne,
I.Sinning,
J.Ståhlberg,
G.Pettersson,
M.Bailey,
M.Siika-Aho,
E.Margolles-Clark,
T.Teeri,
T.A.Jones.
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Ref.
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J Mol Biol, 1993,
234,
905-907.
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PubMed id
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