2d0h
From Proteopedia
(New page: 200px<br /><applet load="2d0h" size="450" color="white" frame="true" align="right" spinBox="true" caption="2d0h, resolution 2.1Å" /> '''Crystal Structure of ...) |
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| - | [[Image:2d0h.gif|left|200px]]<br /><applet load="2d0h" size=" | + | [[Image:2d0h.gif|left|200px]]<br /><applet load="2d0h" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2d0h, resolution 2.1Å" /> | caption="2d0h, resolution 2.1Å" /> | ||
'''Crystal Structure of Thermoactinomyces vulgaris R-47 Alpha-Amylase 1 (TVAI) Mutant D356N/E396Q complexed with P2, a pullulan model oligosaccharide'''<br /> | '''Crystal Structure of Thermoactinomyces vulgaris R-47 Alpha-Amylase 1 (TVAI) Mutant D356N/E396Q complexed with P2, a pullulan model oligosaccharide'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Thermoactinomyces vulgaris R-47 alpha-amylase 1 (TVAI) has unique | + | Thermoactinomyces vulgaris R-47 alpha-amylase 1 (TVAI) has unique hydrolyzing activities for pullulan with sequence repeats of alpha-(1,4), alpha-(1,4), and alpha-(1,6) glycosidic linkages, as well as for starch. TVAI mainly hydrolyzes alpha-(1,4) glycosidic linkages to produce a panose, but it also hydrolyzes alpha-(1,6) glycosidic linkages with a lesser efficiency. X-ray structures of three complexes comprising an inactive mutant TVAI (D356N or D356N/E396Q) and a pullulan model oligosaccharide (P2; [Glc-alpha-(1,6)-Glc-alpha-(1,4)-Glc-alpha-(1,4)]2 or P5; [Glc-alpha-(1,6)-Glc-alpha-(1,4)-Glc-alpha-(1,4)]5) were determined. The complex D356N/P2 is a mimic of the enzyme/product complex in the main catalytic reaction of TVAI, and a structural comparison with Aspergillus oryzaealpha-amylase showed that the (-) subsites of TVAI are responsible for recognizing both starch and pullulan. D356N/E396Q/P2 and D356N/E396Q/P5 provided models of the enzyme/substrate complex recognizing the alpha-(1,6) glycosidic linkage at the hydrolyzing site. They showed that only subsites -1 and -2 at the nonreducing end of TVAI are effective in the hydrolysis of alpha-(1,6) glycosidic linkages, leading to weak interactions between substrates and the enzyme. Domain N of TVAI is a starch-binding domain acting as an anchor in the catalytic reaction of the enzyme. In this study, additional substrates were also found to bind to domain N, suggesting that domain N also functions as a pullulan-binding domain. |
==About this Structure== | ==About this Structure== | ||
| - | 2D0H is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermoactinomyces_vulgaris Thermoactinomyces vulgaris] with CA and MPD as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Alpha-amylase Alpha-amylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.1 3.2.1.1] Full crystallographic information is available from [http:// | + | 2D0H is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermoactinomyces_vulgaris Thermoactinomyces vulgaris] with <scene name='pdbligand=CA:'>CA</scene> and <scene name='pdbligand=MPD:'>MPD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Alpha-amylase Alpha-amylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.1 3.2.1.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2D0H OCA]. |
==Reference== | ==Reference== | ||
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[[Category: alpha-amylase]] | [[Category: alpha-amylase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:54:11 2008'' |
Revision as of 14:54, 21 February 2008
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Crystal Structure of Thermoactinomyces vulgaris R-47 Alpha-Amylase 1 (TVAI) Mutant D356N/E396Q complexed with P2, a pullulan model oligosaccharide
Overview
Thermoactinomyces vulgaris R-47 alpha-amylase 1 (TVAI) has unique hydrolyzing activities for pullulan with sequence repeats of alpha-(1,4), alpha-(1,4), and alpha-(1,6) glycosidic linkages, as well as for starch. TVAI mainly hydrolyzes alpha-(1,4) glycosidic linkages to produce a panose, but it also hydrolyzes alpha-(1,6) glycosidic linkages with a lesser efficiency. X-ray structures of three complexes comprising an inactive mutant TVAI (D356N or D356N/E396Q) and a pullulan model oligosaccharide (P2; [Glc-alpha-(1,6)-Glc-alpha-(1,4)-Glc-alpha-(1,4)]2 or P5; [Glc-alpha-(1,6)-Glc-alpha-(1,4)-Glc-alpha-(1,4)]5) were determined. The complex D356N/P2 is a mimic of the enzyme/product complex in the main catalytic reaction of TVAI, and a structural comparison with Aspergillus oryzaealpha-amylase showed that the (-) subsites of TVAI are responsible for recognizing both starch and pullulan. D356N/E396Q/P2 and D356N/E396Q/P5 provided models of the enzyme/substrate complex recognizing the alpha-(1,6) glycosidic linkage at the hydrolyzing site. They showed that only subsites -1 and -2 at the nonreducing end of TVAI are effective in the hydrolysis of alpha-(1,6) glycosidic linkages, leading to weak interactions between substrates and the enzyme. Domain N of TVAI is a starch-binding domain acting as an anchor in the catalytic reaction of the enzyme. In this study, additional substrates were also found to bind to domain N, suggesting that domain N also functions as a pullulan-binding domain.
About this Structure
2D0H is a Single protein structure of sequence from Thermoactinomyces vulgaris with and as ligands. Active as Alpha-amylase, with EC number 3.2.1.1 Full crystallographic information is available from OCA.
Reference
Complexes of Thermoactinomyces vulgaris R-47 alpha-amylase 1 and pullulan model oligossacharides provide new insight into the mechanism for recognizing substrates with alpha-(1,6) glycosidic linkages., Abe A, Yoshida H, Tonozuka T, Sakano Y, Kamitori S, FEBS J. 2005 Dec;272(23):6145-53. PMID:16302977
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