View source for 4pfh


==Crystal structure of engineered D-tagatose 3-epimerase PcDTE-IDF8==
<StructureSection load='4pfh' size='340' side='right'caption='[[4pfh]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4pfh]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_cichorii Pseudomonas cichorii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4PFH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4PFH 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FUD:D-FRUCTOSE'>FUD</scene>, <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=PSJ:D-PSICOSE'>PSJ</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=4pfh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4pfh OCA], [https://pdbe.org/4pfh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4pfh RCSB], [https://www.ebi.ac.uk/pdbsum/4pfh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4pfh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DT3E_PSECI DT3E_PSECI] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Functional promiscuity of enzymes can often be harnessed as the starting point for the directed evolution of novel biocatalysts. Here we describe the divergent morphing of an engineered thermostable variant (Var8) of a promiscuous D-tagatose epimerase (DTE) into two efficient catalysts for the C3 epimerization of D-fructose to D-psicose and of L-sorbose to L-tagatose. Iterative single-site randomization and screening of 48 residues in the first and second shells around the substrate-binding site of Var8 yielded the eight-site mutant IDF8 (ninefold improved kcat for the epimerization of D-fructose) and the six-site mutant ILS6 (14-fold improved epimerization of L-sorbose), compared to Var8. Structure analysis of IDF8 revealed a charged patch at the entrance of its active site; this presumably facilitates entry of the polar substrate. The improvement in catalytic activity of variant ILS6 is thought to relate to subtle changes in the hydration of the bound substrate. The structures can now be used to select additional sites for further directed evolution of the ketohexose epimerase.

Directed Divergent Evolution of a Thermostable D-Tagatose Epimerase towards Improved Activity for Two Hexose Substrates.,Bosshart A, Hee CS, Bechtold M, Schirmer T, Panke S Chembiochem. 2015 Feb 5. doi: 10.1002/cbic.201402620. PMID:25655925<ref>PMID:25655925</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4pfh" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pseudomonas cichorii]]
[[Category: Bosshart A]]
[[Category: Hee CS]]
[[Category: Schirmer T]]