2a3h
From Proteopedia
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==Overview== | ==Overview== | ||
- | The enzymatic degradation of cellulose, by cellulases, is not only | + | The enzymatic degradation of cellulose, by cellulases, is not only industrially important in the food, paper, and textile industries but also a potentially useful method for the environmentally friendly recycling of municipal waste. An understanding of the structural and mechanistic requirements for the hydrolysis of the beta-1,4 glycosidic bonds of cellulose is an essential prerequisite for beneficial engineering of cellulases for these processes. Cellulases have been classified into 13 of the 62 glycoside hydrolase families [Henrissat, B., and Bairoch, A. (1996) Biochem J. 316, 695-696]. The structure of the catalytic core of the family 5 endoglucanase, Ce15A, from the alkalophilic Bacillus agaradherans has been solved by multiple isomorphous replacement at 1.6 A resolution. Ce15A has the (alpha/beta)8 barrel structure and signature structural features typical of the grouping of glycoside hydrolase families known as clan GH-A, with the catalytic acid/base Glu 139 and nucleophile Glu 228 on barrel strands beta 4 and beta 7 as expected. In addition to the native enzyme, the 2.0 A resolution structure of the cellobiose-bound form of the enzyme has also been determined. Cellobiose binds preferentially in the -2 and -3 subsites of the enzyme. Kinetic studies on the isolated catalytic core domain of Ce15A, using a series of reduced cellodextrins as substrates, suggest approximately five to six binding sites, consistent with the shape and size of the cleft observed by crystallography. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Andersen, K.]] | [[Category: Andersen, K.]] | ||
- | [[Category: Brzozowski, A | + | [[Category: Brzozowski, A M.]] |
- | [[Category: Davies, G | + | [[Category: Davies, G J.]] |
[[Category: Schulein, M.]] | [[Category: Schulein, M.]] | ||
[[Category: CBI]] | [[Category: CBI]] | ||
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[[Category: glycoside hydrolase family 5]] | [[Category: glycoside hydrolase family 5]] | ||
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:23:13 2008'' |
Revision as of 14:23, 21 February 2008
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CELLOBIOSE COMPLEX OF THE ENDOGLUCANASE CEL5A FROM BACILLUS AGARADHERANS AT 2.0 A RESOLUTION
Overview
The enzymatic degradation of cellulose, by cellulases, is not only industrially important in the food, paper, and textile industries but also a potentially useful method for the environmentally friendly recycling of municipal waste. An understanding of the structural and mechanistic requirements for the hydrolysis of the beta-1,4 glycosidic bonds of cellulose is an essential prerequisite for beneficial engineering of cellulases for these processes. Cellulases have been classified into 13 of the 62 glycoside hydrolase families [Henrissat, B., and Bairoch, A. (1996) Biochem J. 316, 695-696]. The structure of the catalytic core of the family 5 endoglucanase, Ce15A, from the alkalophilic Bacillus agaradherans has been solved by multiple isomorphous replacement at 1.6 A resolution. Ce15A has the (alpha/beta)8 barrel structure and signature structural features typical of the grouping of glycoside hydrolase families known as clan GH-A, with the catalytic acid/base Glu 139 and nucleophile Glu 228 on barrel strands beta 4 and beta 7 as expected. In addition to the native enzyme, the 2.0 A resolution structure of the cellobiose-bound form of the enzyme has also been determined. Cellobiose binds preferentially in the -2 and -3 subsites of the enzyme. Kinetic studies on the isolated catalytic core domain of Ce15A, using a series of reduced cellodextrins as substrates, suggest approximately five to six binding sites, consistent with the shape and size of the cleft observed by crystallography.
About this Structure
2A3H is a Single protein structure of sequence from Bacillus agaradhaerens with as ligand. Active as Cellulase, with EC number 3.2.1.4 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Structure of the Bacillus agaradherans family 5 endoglucanase at 1.6 A and its cellobiose complex at 2.0 A resolution., Davies GJ, Dauter M, Brzozowski AM, Bjornvad ME, Andersen KV, Schulein M, Biochemistry. 1998 Feb 17;37(7):1926-32. PMID:9485319
Page seeded by OCA on Thu Feb 21 16:23:13 2008