1qk0
From Proteopedia
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| - | [[Image:1qk0.gif|left|200px]] | + | [[Image:1qk0.gif|left|200px]] |
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| - | '''CEL6A IN COMPLEX WITH M-IODOBENZYL BETA-D-GLUCOPYRANOSYL-BETA(1,4)-D-XYLOPYRANOSIDE''' | + | {{Structure |
| + | |PDB= 1qk0 |SIZE=350|CAPTION= <scene name='initialview01'>1qk0</scene>, resolution 2.10Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</scene>, <scene name='pdbligand=MAN:ALPHA-D-MANNOSE'>MAN</scene>, <scene name='pdbligand=CO:COBALT+(II)+ION'>CO</scene>, <scene name='pdbligand=IOD:IODIDE+ION'>IOD</scene> and <scene name='pdbligand=IOB:3-IODO-BENZYL ALCOHOL'>IOB</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Cellulose_1,4-beta-cellobiosidase Cellulose 1,4-beta-cellobiosidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.91 3.2.1.91] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CEL6A IN COMPLEX WITH M-IODOBENZYL BETA-D-GLUCOPYRANOSYL-BETA(1,4)-D-XYLOPYRANOSIDE''' | ||
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==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1QK0 is a [ | + | 1QK0 is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Hypocrea_jecorina Hypocrea jecorina]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QK0 OCA]. |
==Reference== | ==Reference== | ||
| - | Crystallographic evidence for substrate ring distortion and protein conformational changes during catalysis in cellobiohydrolase Ce16A from trichoderma reesei., Zou J, Kleywegt GJ, Stahlberg J, Driguez H, Nerinckx W, Claeyssens M, Koivula A, Teeri TT, Jones TA, Structure. 1999 Sep 15;7(9):1035-45. PMID:[http:// | + | Crystallographic evidence for substrate ring distortion and protein conformational changes during catalysis in cellobiohydrolase Ce16A from trichoderma reesei., Zou J, Kleywegt GJ, Stahlberg J, Driguez H, Nerinckx W, Claeyssens M, Koivula A, Teeri TT, Jones TA, Structure. 1999 Sep 15;7(9):1035-45. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10508787 10508787] |
[[Category: Cellulose 1,4-beta-cellobiosidase]] | [[Category: Cellulose 1,4-beta-cellobiosidase]] | ||
[[Category: Hypocrea jecorina]] | [[Category: Hypocrea jecorina]] | ||
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[[Category: hydrolase (o-glycosyl)]] | [[Category: hydrolase (o-glycosyl)]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 13:38:38 2008'' |
Revision as of 11:38, 20 March 2008
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| , resolution 2.10Å | |||||||
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| Ligands: | , , , and | ||||||
| Activity: | Cellulose 1,4-beta-cellobiosidase, with EC number 3.2.1.91 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CEL6A IN COMPLEX WITH M-IODOBENZYL BETA-D-GLUCOPYRANOSYL-BETA(1,4)-D-XYLOPYRANOSIDE
Overview
BACKGROUND: Cel6A is one of the two cellobiohydrolases produced by Trichoderma reesei. The catalytic core has a structure that is a variation of the classic TIM barrel. The active site is located inside a tunnel, the roof of which is formed mainly by a pair of loops. RESULTS: We describe three new ligand complexes. One is the structure of the wild-type enzyme in complex with a nonhydrolysable cello-oligosaccharide, methyl 4-S-beta-cellobiosyl-4-thio-beta-cellobioside (Glc)(2)-S-(Glc)(2), which differs from a cellotetraose in the nature of the central glycosidic linkage where a sulphur atom replaces an oxygen atom. The second structure is a mutant, Y169F, in complex with the same ligand, and the third is the wild-type enzyme in complex with m-iodobenzyl beta-D-glucopyranosyl-beta(1,4)-D-xylopyranoside (IBXG). CONCLUSIONS: The (Glc)(2)-S-(Glc)(2) ligand binds in the -2 to +2 sites in both the wild-type and mutant enzymes. The glucosyl unit in the -1 site is distorted from the usual chair conformation in both structures. The IBXG ligand binds in the -2 to +1 sites, with the xylosyl unit in the -1 site where it adopts the energetically favourable chair conformation. The -1 site glucosyl of the (Glc)(2)-S-(Glc)(2) ligand is unable to take on this conformation because of steric clashes with the protein. The crystallographic results show that one of the tunnel-forming loops in Cel6A is sensitive to modifications at the active site, and is able to take on a number of different conformations. One of the conformational changes disrupts a set of interactions at the active site that we propose is an integral part of the reaction mechanism.
About this Structure
1QK0 is a Single protein structure of sequence from Hypocrea jecorina. Full crystallographic information is available from OCA.
Reference
Crystallographic evidence for substrate ring distortion and protein conformational changes during catalysis in cellobiohydrolase Ce16A from trichoderma reesei., Zou J, Kleywegt GJ, Stahlberg J, Driguez H, Nerinckx W, Claeyssens M, Koivula A, Teeri TT, Jones TA, Structure. 1999 Sep 15;7(9):1035-45. PMID:10508787
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