1dtu
From Proteopedia
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| - | [[Image:1dtu.jpg|left|200px]] | + | [[Image:1dtu.jpg|left|200px]] |
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| - | '''BACILLUS CIRCULANS STRAIN 251 CYCLODEXTRIN GLYCOSYLTRANSFERASE: A MUTANT Y89D/S146P COMPLEXED TO AN HEXASACCHARIDE INHIBITOR''' | + | {{Structure |
| + | |PDB= 1dtu |SIZE=350|CAPTION= <scene name='initialview01'>1dtu</scene>, resolution 2.40Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> and <scene name='pdbligand=ADH:1-AMINO-2,3-DIHYDROXY-5-HYDROXYMETHYL CYCLOHEX-5-ENE'>ADH</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] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''BACILLUS CIRCULANS STRAIN 251 CYCLODEXTRIN GLYCOSYLTRANSFERASE: A MUTANT Y89D/S146P COMPLEXED TO AN HEXASACCHARIDE INHIBITOR''' | ||
| + | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1DTU is a [ | + | 1DTU is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_circulans Bacillus circulans]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DTU OCA]. |
==Reference== | ==Reference== | ||
| - | Rational design of cyclodextrin glycosyltransferase from Bacillus circulans strain 251 to increase alpha-cyclodextrin production., van der Veen BA, Uitdehaag JC, Penninga D, van Alebeek GJ, Smith LM, Dijkstra BW, Dijkhuizen L, J Mol Biol. 2000 Mar 3;296(4):1027-38. PMID:[http:// | + | Rational design of cyclodextrin glycosyltransferase from Bacillus circulans strain 251 to increase alpha-cyclodextrin production., van der Veen BA, Uitdehaag JC, Penninga D, van Alebeek GJ, Smith LM, Dijkstra BW, Dijkhuizen L, J Mol Biol. 2000 Mar 3;296(4):1027-38. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10686101 10686101] |
[[Category: Bacillus circulans]] | [[Category: Bacillus circulans]] | ||
[[Category: Cyclomaltodextrin glucanotransferase]] | [[Category: Cyclomaltodextrin glucanotransferase]] | ||
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[[Category: product specificity]] | [[Category: product specificity]] | ||
| - | ''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 10:44:17 2008'' |
Revision as of 08:44, 20 March 2008
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| , resolution 2.40Å | |||||||
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| Ligands: | and | ||||||
| Activity: | Cyclomaltodextrin glucanotransferase, with EC number 2.4.1.19 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
BACILLUS CIRCULANS STRAIN 251 CYCLODEXTRIN GLYCOSYLTRANSFERASE: A MUTANT Y89D/S146P COMPLEXED TO AN HEXASACCHARIDE INHIBITOR
Overview
Cyclodextrin glycosyltransferases (CGTase) (EC 2.4.1.19) are extracellular bacterial enzymes that generate cyclodextrins from starch. All known CGTases produce mixtures of alpha, beta, and gamma-cyclodextrins. A maltononaose inhibitor bound to the active site of the CGTase from Bacillus circulans strain 251 revealed sugar binding subsites, distant from the catalytic residues, which have been proposed to be involved in the cyclodextrin size specificity of these enzymes. To probe the importance of these distant substrate binding subsites for the alpha, beta, and gamma-cyclodextrin product ratios of the various CGTases, we have constructed three single and one double mutant, Y89G, Y89D, S146P and Y89D/S146P, using site-directed mutagenesis. The mutations affected the cyclization, coupling; disproportionation and hydrolyzing reactions of the enzyme. The double mutant Y89D/S146P showed a twofold increase in the production of alpha-cyclodextrin from starch. This mutant protein was crystallized and its X-ray structure, in a complex with a maltohexaose inhibitor, was determined at 2.4 A resolution. The bound maltohexaose molecule displayed a binding different from the maltononaose inhibitor, allowing rationalization of the observed change in product specificity. Hydrogen bonds (S146) and hydrophobic contacts (Y89) appear to contribute strongly to the size of cyclodextrin products formed and thus to CGTase product specificity. Changes in sugar binding subsites -3 and -7 thus result in mutant proteins with changed cyclodextrin production specificity.
About this Structure
1DTU is a Single protein structure of sequence from Bacillus circulans. Full crystallographic information is available from OCA.
Reference
Rational design of cyclodextrin glycosyltransferase from Bacillus circulans strain 251 to increase alpha-cyclodextrin production., van der Veen BA, Uitdehaag JC, Penninga D, van Alebeek GJ, Smith LM, Dijkstra BW, Dijkhuizen L, J Mol Biol. 2000 Mar 3;296(4):1027-38. PMID:10686101
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