1r7a
From Proteopedia
(New page: 200px<br /><applet load="1r7a" size="450" color="white" frame="true" align="right" spinBox="true" caption="1r7a, resolution 1.77Å" /> '''Sucrose Phosphorylas...) |
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| - | [[Image:1r7a.jpg|left|200px]]<br /><applet load="1r7a" size=" | + | [[Image:1r7a.jpg|left|200px]]<br /><applet load="1r7a" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1r7a, resolution 1.77Å" /> | caption="1r7a, resolution 1.77Å" /> | ||
'''Sucrose Phosphorylase from Bifidobacterium adolescentis'''<br /> | '''Sucrose Phosphorylase from Bifidobacterium adolescentis'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Around 80 enzymes are implicated in the generic starch and sucrose | + | Around 80 enzymes are implicated in the generic starch and sucrose pathways. One of these enzymes is sucrose phosphorylase, which reversibly catalyzes the conversion of sucrose and orthophosphate to d-Fructose and alpha-d-glucose 1-phosphate. Here, we present the crystal structure of sucrose phosphorylase from Bifidobacterium adolescentis (BiSP) refined at 1.77 A resolution. It represents the first 3D structure of a sucrose phosphorylase and is the first structure of a phosphate-dependent enzyme from the glycoside hydrolase family 13. The structure of BiSP is composed of the four domains A, B, B', and C. Domain A comprises the (beta/alpha)(8)-barrel common to family 13. The catalytic active-site residues (Asp192 and Glu232) are located at the tips of beta-sheets 4 and 5 in the (beta/alpha)(8)-barrel, as required for family 13 members. The topology of the B' domain disfavors oligosaccharide binding and reduces the size of the substrate access channel compared to other family 13 members, underlining the role of this domain in modulating the function of these enzymes. It is remarkable that the fold of the C domain is not observed in any other known hydrolases of family 13. BiSP was found as a homodimer in the crystal, and a dimer contact surface area of 960 A(2) per monomer was calculated. The majority of the interactions are confined to the two B domains, but interactions between the loop 8 regions of the two barrels are also observed. This results in a large cavity in the dimer, including the entrance to the two active sites. |
==About this Structure== | ==About this Structure== | ||
| - | 1R7A is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bifidobacterium_adolescentis Bifidobacterium adolescentis] with TRS as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Sucrose_phosphorylase Sucrose phosphorylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.7 2.4.1.7] Full crystallographic information is available from [http:// | + | 1R7A is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bifidobacterium_adolescentis Bifidobacterium adolescentis] with <scene name='pdbligand=TRS:'>TRS</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Sucrose_phosphorylase Sucrose phosphorylase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.1.7 2.4.1.7] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1R7A OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Sucrose phosphorylase]] | [[Category: Sucrose phosphorylase]] | ||
| - | [[Category: Broek, L | + | [[Category: Broek, L A.M van den.]] |
[[Category: Gajhede, M.]] | [[Category: Gajhede, M.]] | ||
| - | [[Category: Kastrup, J | + | [[Category: Kastrup, J S.]] |
[[Category: Mirza, O.]] | [[Category: Mirza, O.]] | ||
| - | [[Category: Skov, L | + | [[Category: Skov, L K.]] |
[[Category: Sprogoe, D.]] | [[Category: Sprogoe, D.]] | ||
| - | [[Category: Voragen, A | + | [[Category: Voragen, A G.J.]] |
[[Category: TRS]] | [[Category: TRS]] | ||
[[Category: beta-alpha-barrels]] | [[Category: beta-alpha-barrels]] | ||
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[[Category: glycoside hydrolase]] | [[Category: glycoside hydrolase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:47:51 2008'' |
Revision as of 12:47, 21 February 2008
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Sucrose Phosphorylase from Bifidobacterium adolescentis
Overview
Around 80 enzymes are implicated in the generic starch and sucrose pathways. One of these enzymes is sucrose phosphorylase, which reversibly catalyzes the conversion of sucrose and orthophosphate to d-Fructose and alpha-d-glucose 1-phosphate. Here, we present the crystal structure of sucrose phosphorylase from Bifidobacterium adolescentis (BiSP) refined at 1.77 A resolution. It represents the first 3D structure of a sucrose phosphorylase and is the first structure of a phosphate-dependent enzyme from the glycoside hydrolase family 13. The structure of BiSP is composed of the four domains A, B, B', and C. Domain A comprises the (beta/alpha)(8)-barrel common to family 13. The catalytic active-site residues (Asp192 and Glu232) are located at the tips of beta-sheets 4 and 5 in the (beta/alpha)(8)-barrel, as required for family 13 members. The topology of the B' domain disfavors oligosaccharide binding and reduces the size of the substrate access channel compared to other family 13 members, underlining the role of this domain in modulating the function of these enzymes. It is remarkable that the fold of the C domain is not observed in any other known hydrolases of family 13. BiSP was found as a homodimer in the crystal, and a dimer contact surface area of 960 A(2) per monomer was calculated. The majority of the interactions are confined to the two B domains, but interactions between the loop 8 regions of the two barrels are also observed. This results in a large cavity in the dimer, including the entrance to the two active sites.
About this Structure
1R7A is a Single protein structure of sequence from Bifidobacterium adolescentis with as ligand. Active as Sucrose phosphorylase, with EC number 2.4.1.7 Full crystallographic information is available from OCA.
Reference
Crystal structure of sucrose phosphorylase from Bifidobacterium adolescentis., Sprogoe D, van den Broek LA, Mirza O, Kastrup JS, Voragen AG, Gajhede M, Skov LK, Biochemistry. 2004 Feb 10;43(5):1156-62. PMID:14756551
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