View source for 7ehr


==Levansucrase from Brenneria sp. EniD 312 at 1.33 angstroms resolution==
<StructureSection load='7ehr' size='340' side='right'caption='[[7ehr]], [[Resolution|resolution]] 1.33&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7ehr]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Brenneria_sp._EniD312 Brenneria sp. EniD312]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7EHR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7EHR 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]] 1.33&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1PE:PENTAETHYLENE+GLYCOL'>1PE</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=PE4:2-{2-[2-(2-{2-[2-(2-ETHOXY-ETHOXY)-ETHOXY]-ETHOXY}-ETHOXY)-ETHOXY]-ETHOXY}-ETHANOL'>PE4</scene>, <scene name='pdbligand=PEG:DI(HYDROXYETHYL)ETHER'>PEG</scene>, <scene name='pdbligand=PGE:TRIETHYLENE+GLYCOL'>PGE</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=7ehr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7ehr OCA], [https://pdbe.org/7ehr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7ehr RCSB], [https://www.ebi.ac.uk/pdbsum/7ehr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7ehr ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/G7LSK3_9GAMM G7LSK3_9GAMM] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Microbial levansucrases (LSs, EC 2.4.1.10) have been widely studied for the synthesis of beta-(2,6)-fructans (levan) from sucrose. LSs synthesize levan-type fructo-oligosaccharides, high-molecular-mass levan polymer or combinations of both. Here, we report crystal structures of LS from the G(-)-bacterium Brenneria sp. EniD 312 (Brs-LS) in its apo form, as well as of two mutants (A154S, H327A) targeting positions known to affect LS reaction specificity. In addition, we report a structure of Brs-LS complexed with sucrose, the first crystal structure of a G(-)-LS with a bound substrate. The overall structure of Brs-LS is similar to that of G(-)- and G(+)-LSs, with the nucleophile (D68), transition stabilizer (D225), and a general acid/base (E309) in its active site. The H327A mutant lacks an essential interaction with glucosyl moieties of bound substrates in subsite +1, explaining the observed smaller products synthesized by this mutant. The A154S mutation affects the hydrogen-bond network around the transition stabilizing residue (D225) and the nucleophile (D68), and may affect the affinity of the enzyme for sucrose such that it becomes less effective in transfructosylation. Taken together, this study provides novel insights into the roles of structural elements and residues in the product specificity of LSs.

Crystal Structure of Levansucrase from the Gram-Negative Bacterium Brenneria Provides Insights into Its Product Size Specificity.,Xu W, Ni D, Hou X, Pijning T, Guskov A, Rao Y, Mu W J Agric Food Chem. 2022 Apr 7. doi: 10.1021/acs.jafc.2c01225. PMID:35388691<ref>PMID:35388691</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 7ehr" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Brenneria sp. EniD312]]
[[Category: Large Structures]]
[[Category: Guskov A]]
[[Category: Hou XD]]
[[Category: Mu WM]]
[[Category: Ni DW]]
[[Category: Pijning T]]
[[Category: Rao YJ]]
[[Category: Xu W]]