5xtl: Difference between revisions
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==Crystal Structure of Transketolase in complex with aminopyrimidine and cysteine sulfonic acid adduct from Pichia Stipitis== | |||
<StructureSection load='5xtl' size='340' side='right' caption='[[5xtl]], [[Resolution|resolution]] 1.10Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[5xtl]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5XTL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5XTL FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=8GF:2-methylpyrimidin-4-amine'>8GF</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=P23:PROPYL+TRIHYDROGEN+DIPHOSPHATE'>P23</scene>, <scene name='pdbligand=PEG:DI(HYDROXYETHYL)ETHER'>PEG</scene></td></tr> | |||
<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=OCS:CYSTEINESULFONIC+ACID'>OCS</scene></td></tr> | |||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Transketolase Transketolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.2.1.1 2.2.1.1] </span></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5xtl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5xtl OCA], [http://pdbe.org/5xtl PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5xtl RCSB], [http://www.ebi.ac.uk/pdbsum/5xtl PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5xtl ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[[http://www.uniprot.org/uniprot/TKT_PICST TKT_PICST]] Catalyzes the transfer of a two-carbon ketol group from a ketose donor to an aldose acceptor, via a covalent intermediate with the cofactor thiamine pyrophosphate. | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
It is theoretically plausible that thiazolium mesomerizes to congeners other than carbene in a low effective dielectric binding site; especially given the energetics and uneven electronegativity of carbene groups. However, such a phenomenon has never been reported. Nine crystal structures of transketolase obtained from Pichia stipitis (TKps) are reported with subatomic resolution, where thiazolium displays an extraordinary ring-bending effect. The bent thiazolium congeners correlate with non-Kekule diradicals because there is no gain or loss of electrons. In conjunction with biophysical and biochemical analyses, it is concluded that ring bending is a result of tautomerization of thiazolium with its non- Kekule diradicals, exclusively in the binding site of TKps. The chemophysical properties of these thiazolium mesomers may account for the great variety of reactivities carried out by thiamine-diphosphate-containing (ThDP) enzymes. The stability of ThDP in living systems can be regulated by the levels of substrates, and hydration and dehydration, as well as diradical-mediated oxidative degradation. | |||
The Mesomeric Effect of Thiazolium on non-Kekule Diradicals in Pichia stipitis Transketolase.,Hsu NS, Wang YL, Lin KH, Chang CF, Lyu SY, Hsu LJ, Liu YC, Chang CY, Wu CJ, Li TL Angew Chem Int Ed Engl. 2018 Feb 12;57(7):1802-1807. doi: 10.1002/anie.201709799., Epub 2018 Jan 15. PMID:29243887<ref>PMID:29243887</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
[[Category: | </div> | ||
[[Category: Li, T | <div class="pdbe-citations 5xtl" style="background-color:#fffaf0;"></div> | ||
[[Category: | == References == | ||
[[Category: | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Transketolase]] | |||
[[Category: Hsu, N S]] | |||
[[Category: Li, T L]] | |||
[[Category: Wang, Y L]] | |||
[[Category: Transferase]] | |||
Revision as of 08:29, 25 April 2018
Crystal Structure of Transketolase in complex with aminopyrimidine and cysteine sulfonic acid adduct from Pichia StipitisCrystal Structure of Transketolase in complex with aminopyrimidine and cysteine sulfonic acid adduct from Pichia Stipitis
Structural highlights
Function[TKT_PICST] Catalyzes the transfer of a two-carbon ketol group from a ketose donor to an aldose acceptor, via a covalent intermediate with the cofactor thiamine pyrophosphate. Publication Abstract from PubMedIt is theoretically plausible that thiazolium mesomerizes to congeners other than carbene in a low effective dielectric binding site; especially given the energetics and uneven electronegativity of carbene groups. However, such a phenomenon has never been reported. Nine crystal structures of transketolase obtained from Pichia stipitis (TKps) are reported with subatomic resolution, where thiazolium displays an extraordinary ring-bending effect. The bent thiazolium congeners correlate with non-Kekule diradicals because there is no gain or loss of electrons. In conjunction with biophysical and biochemical analyses, it is concluded that ring bending is a result of tautomerization of thiazolium with its non- Kekule diradicals, exclusively in the binding site of TKps. The chemophysical properties of these thiazolium mesomers may account for the great variety of reactivities carried out by thiamine-diphosphate-containing (ThDP) enzymes. The stability of ThDP in living systems can be regulated by the levels of substrates, and hydration and dehydration, as well as diradical-mediated oxidative degradation. The Mesomeric Effect of Thiazolium on non-Kekule Diradicals in Pichia stipitis Transketolase.,Hsu NS, Wang YL, Lin KH, Chang CF, Lyu SY, Hsu LJ, Liu YC, Chang CY, Wu CJ, Li TL Angew Chem Int Ed Engl. 2018 Feb 12;57(7):1802-1807. doi: 10.1002/anie.201709799., Epub 2018 Jan 15. PMID:29243887[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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