View source for 8jz8


==Subatomic structure of orthorhombic thaumatin at 0.89 Angstroms==
<StructureSection load='8jz8' size='340' side='right'caption='[[8jz8]], [[Resolution|resolution]] 0.89&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[8jz8]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Thaumatococcus_daniellii Thaumatococcus daniellii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=8JZ8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=8JZ8 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]] 0.89&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PEG:DI(HYDROXYETHYL)ETHER'>PEG</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=8jz8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=8jz8 OCA], [https://pdbe.org/8jz8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=8jz8 RCSB], [https://www.ebi.ac.uk/pdbsum/8jz8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=8jz8 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/THM1_THADA THM1_THADA] Taste-modifying protein; intensely sweet-tasting. It is 100000 times sweeter than sucrose on a molar basis.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Thaumatin is a sweet-tasting protein that elicits a sweet taste at a threshold of approximately 50 nM. Structure-sweetness relationships in thaumatin suggest that the basicity of two amino acids residues, Arg82 and Lys67, are particularly responsible for sweetness. Using tetragonal crystals, our structural analysis suggested that flexible sidechain conformations of these two residues play an important role in sweetness. However, in tetragonal crystals, Arg82 is adjacent to symmetry-related residues, and its flexibility is relatively restrained by the crystal packing. To reduce and diminish these symmetry-related effects, orthorhombic crystals were prepared, and their structures were successfully determined at a resolution of 0.89 A. Within the orthorhombic lattice, two alternative conformations were more clearly visible at Lys67 than in a tetragonal system. Interestingly, for the first time, three alternative conformations at Arg82 were only found in an orthorhombic system. These results suggest the importance of flexible conformations in sweetness determinants. Such subtle structural variations might serve to adjust the complementarity of the electrostatic potentials of sweet receptors, thereby eliciting the potent sweet taste of thaumatin.

Subatomic structure of orthorhombic thaumatin at 0.89 A reveals that highly flexible conformations are crucial for thaumatin sweetness.,Masuda T, Suzuki M, Yamasaki M, Mikami B Biochem Biophys Res Commun. 2024 Apr 9;703:149601. doi: , 10.1016/j.bbrc.2024.149601. Epub 2024 Feb 6. PMID:38364680<ref>PMID:38364680</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 8jz8" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Thaumatococcus daniellii]]
[[Category: Masuda T]]
[[Category: Mikami B]]
[[Category: Suzuki M]]
[[Category: Yamasaki M]]