View source for 3vgb


==Crystal structure of glycosyltrehalose trehalohydrolase (GTHase) from Sulfolobus solfataricus KM1==
<StructureSection load='3vgb' size='340' side='right'caption='[[3vgb]], [[Resolution|resolution]] 2.65&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3vgb]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Saccharolobus_solfataricus Saccharolobus solfataricus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3VGB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3VGB FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.65&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FLC:CITRATE+ANION'>FLC</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=3vgb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3vgb OCA], [https://pdbe.org/3vgb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3vgb RCSB], [https://www.ebi.ac.uk/pdbsum/3vgb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3vgb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TREZ_SACSO TREZ_SACSO] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Glycosyltrehalose trehalohydrolase (GTHase) is an alpha-amylase that cleaves the alpha-1,4 bond adjacent to the alpha-1,1 bond of maltooligosyltrehalose to release trehalose. To investigate the catalytic and substrate recognition mechanisms of GTHase, two residues, Asp252 (nucleophile) and Glu283 (general acid/base), located at the catalytic site of GTHase were mutated (Asp252--&gt;Ser (D252S), Glu (D252E) and Glu283--&gt;Gln (E283Q)), and the activity and structure of the enzyme were investigated. The E283Q, D252E, and D252S mutants showed only 0.04, 0.03, and 0.6% of enzymatic activity against the wild-type, respectively. The crystal structure of the E283Q mutant GTHase in complex with the substrate, maltotriosyltrehalose (G3-Tre), was determined to 2.6-A resolution. The structure with G3-Tre indicated that GTHase has at least five substrate binding subsites and that Glu283 is the catalytic acid, and Asp252 is the nucleophile that attacks the C1 carbon in the glycosidic linkage of G3-Tre. The complex structure also revealed a scheme for substrate recognition by GTHase. Substrate recognition involves two unique interactions: stacking of Tyr325 with the terminal glucose ring of the trehalose moiety and perpendicularly placement of Trp215 to the pyranose rings at the subsites -1 and +1 glucose.

Substrate recognition mechanism of a glycosyltrehalose trehalohydrolase from Sulfolobus solfataricus KM1.,Okazaki N, Tamada T, Feese MD, Kato M, Miura Y, Komeda T, Kobayashi K, Kondo K, Blaber M, Kuroki R Protein Sci. 2012 Apr;21(4):539-52. doi: 10.1002/pro.2039. Epub 2012 Feb 28. PMID:22334583<ref>PMID:22334583</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3vgb" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Saccharolobus solfataricus]]
[[Category: Feese MD]]
[[Category: Kato M]]
[[Category: Kobayashi K]]
[[Category: Komeda T]]
[[Category: Kondo K]]
[[Category: Kuroki R]]
[[Category: Miura Y]]
[[Category: Okazaki N]]
[[Category: Tamada T]]