2dtd: Difference between revisions
m Protected "2dtd" [edit=sysop:move=sysop] |
No edit summary |
||
Line 1: | Line 1: | ||
[[Image: | ==Structure of Thermoplasma acidophilum aldohexose dehydrogenase (AldT) in ligand-free form== | ||
<StructureSection load='2dtd' size='340' side='right' caption='[[2dtd]], [[Resolution|resolution]] 2.10Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2dtd]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Thermoplasma_acidophilum Thermoplasma acidophilum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2DTD OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2DTD FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2dte|2dte]]</td></tr> | |||
<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">Ta0754 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=2303 Thermoplasma acidophilum])</td></tr> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucose_1-dehydrogenase_(NAD(+)) Glucose 1-dehydrogenase (NAD(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.118 1.1.1.118] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2dtd FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2dtd OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2dtd RCSB], [http://www.ebi.ac.uk/pdbsum/2dtd PDBsum]</span></td></tr> | |||
<table> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/dt/2dtd_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The D-aldohexose dehydrogenase from the thermoacidophilic archaea Thermoplasma acidophilum (AldT) belongs to the short-chain dehydrogenase/reductase (SDR) superfamily and catalyzes the oxidation of several monosaccharides with a preference for NAD(+) rather than NADP(+) as a cofactor. It has been found that AldT is a unique enzyme that exhibits the highest dehydrogenase activity against D-mannose. Here, we describe the crystal structures of AldT in ligand-free form, in complex with NADH, and in complex with the substrate D-mannose, at 2.1 A, 1.65 A, and 1.6 A resolution, respectively. The AldT subunit forms a typical SDR fold with an unexpectedly long C-terminal tail and assembles into an intertwined tetramer. The D-mannose complex structure reveals that Glu84 interacts with the axial C2 hydroxyl group of the bound D-mannose. Structural comparison with Bacillus megaterium glucose dehydrogenase (BmGlcDH) suggests that the conformation of the glutamate side-chain is crucial for discrimination between D-mannose and its C2 epimer D-glucose, and the conformation of the glutamate side-chain depends on the spatial arrangement of nearby hydrophobic residues that do not directly interact with the substrate. Elucidation of the D-mannose recognition mechanism of AldT further provides structural insights into the unique substrate selectivity of AldT. Finally, we show that the extended C-terminal tail completely shuts the substrate-binding pocket of the neighboring subunit both in the presence and absence of substrate. The elaborate inter-subunit interactions between the C-terminal tail and the entrance of the substrate-binding pocket imply that the tail may play a pivotal role in the enzyme activity. | |||
Structural insights into unique substrate selectivity of Thermoplasma acidophilum D-aldohexose dehydrogenase.,Yasutake Y, Nishiya Y, Tamura N, Tamura T J Mol Biol. 2007 Apr 6;367(4):1034-46. Epub 2007 Jan 16. PMID:17300803<ref>PMID:17300803</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
== | |||
< | |||
[[Category: Thermoplasma acidophilum]] | [[Category: Thermoplasma acidophilum]] | ||
[[Category: Nishiya, Y.]] | [[Category: Nishiya, Y.]] |
Revision as of 05:10, 30 September 2014
Structure of Thermoplasma acidophilum aldohexose dehydrogenase (AldT) in ligand-free formStructure of Thermoplasma acidophilum aldohexose dehydrogenase (AldT) in ligand-free form
Structural highlights
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 PubMedThe D-aldohexose dehydrogenase from the thermoacidophilic archaea Thermoplasma acidophilum (AldT) belongs to the short-chain dehydrogenase/reductase (SDR) superfamily and catalyzes the oxidation of several monosaccharides with a preference for NAD(+) rather than NADP(+) as a cofactor. It has been found that AldT is a unique enzyme that exhibits the highest dehydrogenase activity against D-mannose. Here, we describe the crystal structures of AldT in ligand-free form, in complex with NADH, and in complex with the substrate D-mannose, at 2.1 A, 1.65 A, and 1.6 A resolution, respectively. The AldT subunit forms a typical SDR fold with an unexpectedly long C-terminal tail and assembles into an intertwined tetramer. The D-mannose complex structure reveals that Glu84 interacts with the axial C2 hydroxyl group of the bound D-mannose. Structural comparison with Bacillus megaterium glucose dehydrogenase (BmGlcDH) suggests that the conformation of the glutamate side-chain is crucial for discrimination between D-mannose and its C2 epimer D-glucose, and the conformation of the glutamate side-chain depends on the spatial arrangement of nearby hydrophobic residues that do not directly interact with the substrate. Elucidation of the D-mannose recognition mechanism of AldT further provides structural insights into the unique substrate selectivity of AldT. Finally, we show that the extended C-terminal tail completely shuts the substrate-binding pocket of the neighboring subunit both in the presence and absence of substrate. The elaborate inter-subunit interactions between the C-terminal tail and the entrance of the substrate-binding pocket imply that the tail may play a pivotal role in the enzyme activity. Structural insights into unique substrate selectivity of Thermoplasma acidophilum D-aldohexose dehydrogenase.,Yasutake Y, Nishiya Y, Tamura N, Tamura T J Mol Biol. 2007 Apr 6;367(4):1034-46. Epub 2007 Jan 16. PMID:17300803[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
|