View source for 4ffh


==Crystal Structure of Levan Fructotransferase D54N mutant from Arthrobacter ureafaciens in complex with sucrose==
<StructureSection load='4ffh' size='340' side='right'caption='[[4ffh]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4ffh]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Paenarthrobacter_ureafaciens Paenarthrobacter ureafaciens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4FFH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4FFH 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FRU:FRUCTOSE'>FRU</scene>, <scene name='pdbligand=GLC:ALPHA-D-GLUCOSE'>GLC</scene>, <scene name='pdbligand=PRD_900003:sucrose'>PRD_900003</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=4ffh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ffh OCA], [https://pdbe.org/4ffh PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4ffh RCSB], [https://www.ebi.ac.uk/pdbsum/4ffh PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4ffh ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/Q9KJD0_PAEUR Q9KJD0_PAEUR] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Levan is beta-2,6-linked polymeric fructose and serves as reserve carbohydrate in some plants and microorganisms. Mobilization of fructose is usually mediated by enzymes such as glycoside hydrolase (GH), typically releasing a monosaccharide as a product. The enzyme levan fructotransferase (LFTase) of the GH32 family catalyzes an intramolecular fructosyl transfer reaction and results in production of cyclic difructose dianhydride, thus exhibiting a novel substrate-specificity. The mechanism by which LFTase carries out these functions via the structural fold conserved in the GH32 family is unknown. Here, we report the crystal structure of LFTase from Arthrobacter ureafaciens in apo form, as well as in complexes with sucrose and levanbiose, a difructosacchride with a beta-2,6-glycosidic linkage. Despite the similarity of its two-domain structure to members of the GH32 family, LFTase contains an active site that accommodates a difructosaccharide using the -1 and -2 subsites. This feature is unique among GH32 proteins and is facilitated by small side-chain residues in the loop region of a catalytic beta-propeller N-domain, which is conserved in the LFTase family. An additional oligosaccharide binding site was also characterized in the beta-sandwich C-domain, supporting its role in carbohydrate recognition. Together with functional analysis, our data provide a molecular basis for the catalytic mechanism of LFTase and suggest functional variations from other GH32 family proteins, notwithstanding the conserved structural elements.

Structural and functional basis for substrate specificity and catalysis of levan fructotransferase.,Park J, Kim MI, Park YD, Shin I, Cha J, Kim CH, Rhee S J Biol Chem. 2012 Jul 18. PMID:22810228<ref>PMID:22810228</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4ffh" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Paenarthrobacter ureafaciens]]
[[Category: Park J]]
[[Category: Rhee S]]