1cgu
From Proteopedia
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|PDB= 1cgu |SIZE=350|CAPTION= <scene name='initialview01'>1cgu</scene>, resolution 2.5Å | |PDB= 1cgu |SIZE=350|CAPTION= <scene name='initialview01'>1cgu</scene>, resolution 2.5Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand=CA:CALCIUM ION'>CA</scene> | + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=GLC:GLUCOSE'>GLC</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/Cyclomaltodextrin_glucanotransferase Cyclomaltodextrin glucanotransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.19 2.4.1.19] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Cyclomaltodextrin_glucanotransferase Cyclomaltodextrin glucanotransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.19 2.4.1.19] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1cgu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cgu OCA], [http://www.ebi.ac.uk/pdbsum/1cgu PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1cgu RCSB]</span> | ||
}} | }} | ||
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[[Category: Klein, C.]] | [[Category: Klein, C.]] | ||
[[Category: Schulz, G E.]] | [[Category: Schulz, G E.]] | ||
| - | [[Category: CA]] | ||
[[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 19:21:31 2008'' |
Revision as of 16:21, 30 March 2008
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| , resolution 2.5Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Activity: | Cyclomaltodextrin glucanotransferase, with EC number 2.4.1.19 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CATALYTIC CENTER OF CYCLODEXTRIN GLYCOSYLTRANSFERASE DERIVED FROM X-RAY STRUCTURE ANALYSIS COMBINED WITH SITE-DIRECTED MUTAGENESIS
Overview
An X-ray structure analysis of a crystal of mutant Asp229----Ala of cyclodextrin glycosyltransferase from Bacillus circulans (Ec 2.4.1.19) that had been shortly exposed to beta-cyclodextrin showed density corresponding to a maltose bound at the catalytic center. The crystal structure was refined to an R-factor of 18.7% at 2.5-A resolution. The catalytic center is defined by homology with the structurally known alpha-amylases and by the observation that mutants Asp229----Ala and Asp328----Ala are almost inactive. By model building, the density-defined maltose was extended to a full beta-cyclodextrin, which then indicated the general locations of seven subsites for glucosyl units. The catalytically competent residues Asp229, Glu257, and Asp328 are at the reducing end of the density-defined maltose. In the unligated wild-type structure, Glu257 and Asp328 form a 2.6-A hydrogen bond between their carboxylates in an arrangement that resembles those of the catalytically competent carboxylates in acid proteases. Presumably, the first catalytic step is an attack of the proton between Glu257 and Asp328 on the oxygen of the glycosidic bond.
About this Structure
1CGU is a Single protein structure of sequence from Bacillus circulans. Full crystallographic information is available from OCA.
Reference
Catalytic center of cyclodextrin glycosyltransferase derived from X-ray structure analysis combined with site-directed mutagenesis., Klein C, Hollender J, Bender H, Schulz GE, Biochemistry. 1992 Sep 22;31(37):8740-6. PMID:1390660
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