1cem
From Proteopedia
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|SITE= | |SITE= | ||
|LIGAND= | |LIGAND= | ||
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Cellulase Cellulase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.4 3.2.1.4] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Cellulase Cellulase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.4 3.2.1.4] </span> |
|GENE= CELA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1515 Clostridium thermocellum]) | |GENE= CELA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1515 Clostridium thermocellum]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1cem FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cem OCA], [http://www.ebi.ac.uk/pdbsum/1cem PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1cem RCSB]</span> | ||
}} | }} | ||
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[[Category: glycosyltransferase]] | [[Category: glycosyltransferase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:20:14 2008'' |
Revision as of 16:20, 30 March 2008
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| , resolution 1.65Å | |||||||
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| Gene: | CELA (Clostridium thermocellum) | ||||||
| Activity: | Cellulase, with EC number 3.2.1.4 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
ENDOGLUCANASE A (CELA) CATALYTIC CORE, RESIDUES 33-395
Overview
BACKGROUND. Cellulases, which catalyze the hydrolysis of glycosidic bonds in cellulose, can be classified into several different protein families. Endoglucanase CelA is a member of glycosyl hydrolase family 8, a family for which no structural information was previously available. RESULTS. The crystal structure of CelA was determined by multiple isomorphous replacement and refined to 1.65 A resolution. The protein folds into a regular (alpha/alpha)6 barrel formed by six inner and six outer alpha helices. Cello-oligosaccharides bind to an acidic cleft containing at least five D-glucosyl-binding subsites (A-E) such that the scissile glycosidic linkage lies between subsites C and D. The strictly conserved residue Glu95, which occupies the center of the substrate-binding cleft and is hydrogen bonded to the glycosidic oxygen, has been assigned the catalytic role of proton donor. CONCLUSIONS. The present analysis provides a basis for modeling homologous family 8 cellulases. The architecture of the active-site cleft, presenting at least five glucosyl-binding subsites, explains why family 8 cellulases cleave cello-oligosaccharide polymers that are at least five D-glycosyl subunits long. Furthermore, the structure of CelA allows comparison with (alpha/alpha)6 barrel glycosidases that are not related in sequence, suggesting a possible, albeit distant, evolutionary relationship between different families of glycosyl hydrolases.
About this Structure
1CEM is a Single protein structure of sequence from Clostridium thermocellum. Full crystallographic information is available from OCA.
Reference
The crystal structure of endoglucanase CelA, a family 8 glycosyl hydrolase from Clostridium thermocellum., Alzari PM, Souchon H, Dominguez R, Structure. 1996 Mar 15;4(3):265-75. PMID:8805535
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