2d2o: Difference between revisions
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==Structure of a complex of Thermoactinomyces vulgaris R-47 alpha-amylase 2 with maltohexaose demonstrates the important role of aromatic residues at the reducing end of the substrate binding cleft== | ==Structure of a complex of Thermoactinomyces vulgaris R-47 alpha-amylase 2 with maltohexaose demonstrates the important role of aromatic residues at the reducing end of the substrate binding cleft== | ||
<StructureSection load='2d2o' size='340' side='right' caption='[[2d2o]], [[Resolution|resolution]] 2.10Å' scene=''> | <StructureSection load='2d2o' size='340' side='right'caption='[[2d2o]], [[Resolution|resolution]] 2.10Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2d2o]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_43649 Atcc 43649]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2D2O OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2D2O FirstGlance]. <br> | <table><tr><td colspan='2'>[[2d2o]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_43649 Atcc 43649]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2D2O OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2D2O FirstGlance]. <br> | ||
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==See Also== | ==See Also== | ||
*[[Amylase|Amylase]] | *[[Amylase 3D structures|Amylase 3D structures]] | ||
== References == | == References == | ||
<references/> | <references/> | ||
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</StructureSection> | </StructureSection> | ||
[[Category: Atcc 43649]] | [[Category: Atcc 43649]] | ||
[[Category: Large Structures]] | |||
[[Category: Neopullulanase]] | [[Category: Neopullulanase]] | ||
[[Category: Kamitori, S]] | [[Category: Kamitori, S]] |
Revision as of 10:52, 4 March 2020
Structure of a complex of Thermoactinomyces vulgaris R-47 alpha-amylase 2 with maltohexaose demonstrates the important role of aromatic residues at the reducing end of the substrate binding cleftStructure of a complex of Thermoactinomyces vulgaris R-47 alpha-amylase 2 with maltohexaose demonstrates the important role of aromatic residues at the reducing end of the substrate binding cleft
Structural highlights
Function[NEPU2_THEVU] Hydrolyzes pullulan efficiently but only a small amount of starch. Endohydrolysis of 1,4-alpha-glucosidic linkages in pullulan to form panose. Cleaves also (1-6)-alpha-glucosidic linkages to form maltotriose. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThermoactinomyces vulgaris R-47 alpha-amylase 2 (TVAII) can efficiently hydrolyze both starch and cyclomaltooligosaccharides (cyclodextrins). The crystal structure of an inactive mutant TVAII in a complex with maltohexaose was determined at a resolution of 2.1A. TVAII adopts a dimeric structure to form two catalytic sites, where substrates are found to bind. At the catalytic site, there are many hydrogen bonds between the enzyme and substrate at the non-reducing end from the hydrolyzing site, but few hydrogen bonds at the reducing end, where two aromatic residues, Trp356 and Tyr45, make effective interactions with a substrate. Trp356 drastically changes its side-chain conformation to achieve a strong stacking interaction with the substrate, and Tyr45 from another molecule forms a water-mediated hydrogen bond with the substrate. Kinetic analysis of the wild-type and mutant enzymes in which Trp356 and/or Tyr45 were replaced with Ala suggested that Trp356 and Tyr45 are essential to the catalytic reaction of the enzyme, and that the formation of a dimeric structure is indispensable for TVAII to hydrolyze both starch and cyclodextrins. Structure of a complex of Thermoactinomyces vulgaris R-47 alpha-amylase 2 with maltohexaose demonstrates the important role of aromatic residues at the reducing end of the substrate binding cleft.,Ohtaki A, Mizuno M, Yoshida H, Tonozuka T, Sakano Y, Kamitori S Carbohydr Res. 2006 Jun 12;341(8):1041-6. Epub 2006 Mar 27. PMID:16564038[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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