1gkk
From Proteopedia
(New page: 200px<br /><applet load="1gkk" size="450" color="white" frame="true" align="right" spinBox="true" caption="1gkk, resolution 1.60Å" /> '''FERULOYL ESTERASE DO...) |
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| - | [[Image:1gkk.gif|left|200px]]<br /><applet load="1gkk" size=" | + | [[Image:1gkk.gif|left|200px]]<br /><applet load="1gkk" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1gkk, resolution 1.60Å" /> | caption="1gkk, resolution 1.60Å" /> | ||
'''FERULOYL ESTERASE DOMAIN OF XYNY FROM CLOSTRIDIUM THERMOCELLUM'''<br /> | '''FERULOYL ESTERASE DOMAIN OF XYNY FROM CLOSTRIDIUM THERMOCELLUM'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: Degradation of the plant cell wall requires the synergistic | + | BACKGROUND: Degradation of the plant cell wall requires the synergistic action of a consortium of predominantly modular enzymes. In Clostridiae, these biocatalysts are organized into a supramolecular assembly termed a "cellulosome." This multienzyme complex possesses, in addition to its well-described cellulolytic activity, an apparatus specific for xylan degradation. Cinnamic acid esterases hydrolyze the ferulate groups involved in the crosslinking of arabinoxylans to lignin and thus play a key role in the degradation of the plant cell wall in addition to having promising industrial and medical applications. RESULTS: We have cloned and overexpressed the feruloyl esterase module from a 5 domain xylanase, Xyn10B from Clostridium thermocellum. The native structure at 1.6 A resolution has been solved with selenomethionine multiple wavelength anomalous dispersion and refined to a final R(free) of 17.8%. The structure of a hydrolytically inactive mutant, S954A, in complex with the reaction product ferulic acid has been refined at a resolution of 1.4 A with an R(free) of 16.0%. CONCLUSIONS: The C. thermocellum Xyn10B ferulic acid esterase displays the alpha/beta-hydrolase fold and possesses a classical Ser-His-Asp catalytic triad. Ferulate esterases are characterized by their specificity, and the active center reveals the binding site for ferulic acid and related compounds. Ferulate binds in a small surface depression that possesses specificity determinants for both the methoxy and hydroxyl ring substituents of the substrate. There appears to be a lack of specificity for the xylan backbone, which may reflect the intrinsic chemical heterogeneity of the natural substrate. |
==About this Structure== | ==About this Structure== | ||
| - | 1GKK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Clostridium_thermocellum Clostridium thermocellum] with CD and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Endo-1,4-beta-xylanase Endo-1,4-beta-xylanase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.8 3.2.1.8] Full crystallographic information is available from [http:// | + | 1GKK is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Clostridium_thermocellum Clostridium thermocellum] with <scene name='pdbligand=CD:'>CD</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Endo-1,4-beta-xylanase Endo-1,4-beta-xylanase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.8 3.2.1.8] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1GKK OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Endo-1,4-beta-xylanase]] | [[Category: Endo-1,4-beta-xylanase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Charnock, S | + | [[Category: Charnock, S J.]] |
| - | [[Category: Davies, G | + | [[Category: Davies, G J.]] |
| - | [[Category: Ferreira, L | + | [[Category: Ferreira, L M.A.]] |
| - | [[Category: Fontes, C | + | [[Category: Fontes, C M.G A.]] |
| - | [[Category: Prates, J | + | [[Category: Prates, J A.M.]] |
[[Category: Tarbouriech, N.]] | [[Category: Tarbouriech, N.]] | ||
[[Category: CD]] | [[Category: CD]] | ||
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[[Category: x-ray crystallography]] | [[Category: x-ray crystallography]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:51:05 2008'' |
Revision as of 10:51, 21 February 2008
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FERULOYL ESTERASE DOMAIN OF XYNY FROM CLOSTRIDIUM THERMOCELLUM
Overview
BACKGROUND: Degradation of the plant cell wall requires the synergistic action of a consortium of predominantly modular enzymes. In Clostridiae, these biocatalysts are organized into a supramolecular assembly termed a "cellulosome." This multienzyme complex possesses, in addition to its well-described cellulolytic activity, an apparatus specific for xylan degradation. Cinnamic acid esterases hydrolyze the ferulate groups involved in the crosslinking of arabinoxylans to lignin and thus play a key role in the degradation of the plant cell wall in addition to having promising industrial and medical applications. RESULTS: We have cloned and overexpressed the feruloyl esterase module from a 5 domain xylanase, Xyn10B from Clostridium thermocellum. The native structure at 1.6 A resolution has been solved with selenomethionine multiple wavelength anomalous dispersion and refined to a final R(free) of 17.8%. The structure of a hydrolytically inactive mutant, S954A, in complex with the reaction product ferulic acid has been refined at a resolution of 1.4 A with an R(free) of 16.0%. CONCLUSIONS: The C. thermocellum Xyn10B ferulic acid esterase displays the alpha/beta-hydrolase fold and possesses a classical Ser-His-Asp catalytic triad. Ferulate esterases are characterized by their specificity, and the active center reveals the binding site for ferulic acid and related compounds. Ferulate binds in a small surface depression that possesses specificity determinants for both the methoxy and hydroxyl ring substituents of the substrate. There appears to be a lack of specificity for the xylan backbone, which may reflect the intrinsic chemical heterogeneity of the natural substrate.
About this Structure
1GKK is a Single protein structure of sequence from Clostridium thermocellum with and as ligands. Active as Endo-1,4-beta-xylanase, with EC number 3.2.1.8 Full crystallographic information is available from OCA.
Reference
The structure of the feruloyl esterase module of xylanase 10B from Clostridium thermocellum provides insights into substrate recognition., Prates JA, Tarbouriech N, Charnock SJ, Fontes CM, Ferreira LM, Davies GJ, Structure. 2001 Dec;9(12):1183-90. PMID:11738044
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