2pak
From Proteopedia
(New page: 200px<br /><applet load="2pak" size="350" color="white" frame="true" align="right" spinBox="true" caption="2pak, resolution 2.40Å" /> '''Structure of a H51N ...) |
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==Overview== | ==Overview== | ||
| - | The repeating unit of the glycan chain in the S-layer of the bacterium | + | The repeating unit of the glycan chain in the S-layer of the bacterium Aneurinibacillus thermoaerophilus L420-91(T) is composed of four alpha-d-rhamnose molecules and two 3-acetamido-3,6-dideoxy-alpha-d-galactose moieties (abbreviated as Fucp3NAc). Formation of the glycan layer requires nucleotide-activated sugars as the donor molecules. Whereas the enzymes involved in the synthesis of GDP-rhamnose have been well characterized, less is known regarding the structures and enzymatic mechanisms of the enzymes required for the production of dTDP-Fucp3NAc. One of the enzymes involved in the biosynthesis of dTDP-Fucp3NAc is a 3,4-ketoisomerase, hereafter referred to as FdtA. Here we describe the first three-dimensional structure of this sugar isomerase complexed with dTDP and solved to 1.5 A resolution. The FdtA dimer assumes an almost jellyfish-like appearance with the sole alpha-helices representing the tentacles. Formation of the FdtA dimer represents a classical example of domain swapping whereby beta-strands 2 and 3 from one subunit form part of a beta-sheet in the second subunit. The active site architecture of FdtA is characterized by a cluster of three histidine residues, two of which, His(49) and His(51), appear to be strictly conserved in the amino acid sequences deposited to date. Site-directed mutagenesis experiments, enzymatic assays, and x-ray crystallographic analyses suggest that His(49) functions as an active site base. |
==About this Structure== | ==About this Structure== | ||
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==Reference== | ==Reference== | ||
| - | The | + | The x-ray structure of dTDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase., Davis ML, Thoden JB, Holden HM, J Biol Chem. 2007 Jun 29;282(26):19227-36. Epub 2007 Apr 25. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=17459872 17459872] |
[[Category: Aneurinibacillus thermoaerophilus]] | [[Category: Aneurinibacillus thermoaerophilus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Davis, M | + | [[Category: Davis, M L.]] |
| - | [[Category: Holden, H | + | [[Category: Holden, H M.]] |
| - | [[Category: Thoden, J | + | [[Category: Thoden, J B.]] |
[[Category: TYD]] | [[Category: TYD]] | ||
[[Category: deoxysugar biosynthesis]] | [[Category: deoxysugar biosynthesis]] | ||
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[[Category: s-layer biosynthesis]] | [[Category: s-layer biosynthesis]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:27:41 2008'' |
Revision as of 16:27, 21 February 2008
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Structure of a H51N mutant dTDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase from Aneurinibacillus thermoaerophilus complexed with TDP
Overview
The repeating unit of the glycan chain in the S-layer of the bacterium Aneurinibacillus thermoaerophilus L420-91(T) is composed of four alpha-d-rhamnose molecules and two 3-acetamido-3,6-dideoxy-alpha-d-galactose moieties (abbreviated as Fucp3NAc). Formation of the glycan layer requires nucleotide-activated sugars as the donor molecules. Whereas the enzymes involved in the synthesis of GDP-rhamnose have been well characterized, less is known regarding the structures and enzymatic mechanisms of the enzymes required for the production of dTDP-Fucp3NAc. One of the enzymes involved in the biosynthesis of dTDP-Fucp3NAc is a 3,4-ketoisomerase, hereafter referred to as FdtA. Here we describe the first three-dimensional structure of this sugar isomerase complexed with dTDP and solved to 1.5 A resolution. The FdtA dimer assumes an almost jellyfish-like appearance with the sole alpha-helices representing the tentacles. Formation of the FdtA dimer represents a classical example of domain swapping whereby beta-strands 2 and 3 from one subunit form part of a beta-sheet in the second subunit. The active site architecture of FdtA is characterized by a cluster of three histidine residues, two of which, His(49) and His(51), appear to be strictly conserved in the amino acid sequences deposited to date. Site-directed mutagenesis experiments, enzymatic assays, and x-ray crystallographic analyses suggest that His(49) functions as an active site base.
About this Structure
2PAK is a Single protein structure of sequence from Aneurinibacillus thermoaerophilus with as ligand. Full crystallographic information is available from OCA.
Reference
The x-ray structure of dTDP-4-keto-6-deoxy-D-glucose-3,4-ketoisomerase., Davis ML, Thoden JB, Holden HM, J Biol Chem. 2007 Jun 29;282(26):19227-36. Epub 2007 Apr 25. PMID:17459872
Page seeded by OCA on Thu Feb 21 18:27:41 2008
