6wn6: Difference between revisions

<table><tr><td colspan='2'>[[6wn6]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_coli"_migula_1895 "bacillus coli" migula 1895]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6WN6 OCA]. For a <b>guided tour on the structure components</b> use [http://proteopedia.org/fgij/fg.htm?mol=6WN6 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene></td></tr>

<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">ycjR, PGD_01932 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 "Bacillus coli" Migula 1895])</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://proteopedia.org/fgij/fg.htm?mol=6wn6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6wn6 OCA], [http://pdbe.org/6wn6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6wn6 RCSB], [http://www.ebi.ac.uk/pdbsum/6wn6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6wn6 ProSAT]</span></td></tr>

== Publication Abstract from PubMed ==

YcjR from Escherichia coli K-12 MG1655 catalyzes the manganese-dependent reversible epimerization of 3-keto-alpha-d-gulosides to the corresponding 3-keto-alpha-d-glucosides as a part of a proposed catabolic pathway for the transformation of d-gulosides to d-glucosides. The three-dimensional structure of the manganese-bound enzyme was determined by X-ray crystallography. The divalent manganese ion is coordinated to the enzyme by ligation to Glu-146, Asp-179, His-205, and Glu-240. When either of the two active site glutamate residues is mutated to glutamine, the enzyme loses all catalytic activity for the epimerization of alpha-methyl-3-keto-d-glucoside at C4. However, the E240Q mutant can catalyze hydrogen-deuterium exchange of the proton at C4 of alpha-methyl-3-keto-d-glucoside in solvent D2O. The E146Q mutant does not catalyze this exchange reaction. These results indicate that YcjR catalyzes the isomerization of 3-keto-d-glucosides via proton abstraction at C4 by Glu-146 to form a cis-enediolate intermediate that is subsequently protonated on the opposite face by Glu-240 to generate the corresponding 3-keto-d-guloside. This conclusion is supported by docking of the cis-enediolate intermediate into the active site of YcjR based on the known binding orientation of d-fructose and d-psicose in the active site of d-psicose-3-epimerase.

 

Structure and Reaction Mechanism of YcjR, an Epimerase That Facilitates the Interconversion of d-Gulosides to d-Glucosides in Escherichia coli.,Mabanglo MF, Huddleston JP, Mukherjee K, Taylor ZW, Raushel FM Biochemistry. 2020 Jun 9;59(22):2069-2077. doi: 10.1021/acs.biochem.0c00334. Epub, 2020 May 28. PMID:32437133<ref>PMID:32437133</ref>

 

<div class="pdbe-citations 6wn6" style="background-color:#fffaf0;"></div>

[[Category: Bacillus coli migula 1895]]

[[Category: Mabanglo, M F]]

[[Category: Mukherjee, K]]

[[Category: Raushel, F M]]

[[Category: Prebiotic]]