View source for 5csy


==Disproportionating enzyme 1 from Arabidopsis - acarbose soak==
<StructureSection load='5csy' size='340' side='right'caption='[[5csy]], [[Resolution|resolution]] 2.05&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[5csy]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5CSY OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5CSY 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]] 2.05&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=AC1:6-METHYL-5-(4,5,6-TRIHYDROXY-3-HYDROXYMETHYL-CYCLOHEX-2-ENYLAMINO)-TETRAHYDRO-PYRAN-2,3,4-TRIOL'>AC1</scene>, <scene name='pdbligand=BGC:BETA-D-GLUCOSE'>BGC</scene>, <scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=GLC:ALPHA-D-GLUCOSE'>GLC</scene>, <scene name='pdbligand=PRD_900065:beta-maltotriose'>PRD_900065</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=5csy FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5csy OCA], [https://pdbe.org/5csy PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5csy RCSB], [https://www.ebi.ac.uk/pdbsum/5csy PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5csy ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DPE1_ARATH DPE1_ARATH] Chloroplastic alpha-glucanotransferase involved in maltotriose metabolism. Probably uses maltotriose as substrate to transfer a maltosyl unit from one molecule to another, resulting in glucose and maltopentaose. The latter can then be further metabolized to maltose and maltotriose by beta-amylase. Required for normal starch degradation in leaves.<ref>PMID:11359613</ref> <ref>PMID:19946617</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The degradation of transitory starch in the chloroplast to provide fuel for the plant during the night requires a suite of enzymes that generate a series of short chain linear glucans. However, glucans of less than four glucose units are no longer substrates for these enzymes, whereas export from the plastid is only possible in the form of either maltose or glucose. In order to make use of maltotriose, which would otherwise accumulate, disproportionating enzyme 1 (DPE1; a 4-alpha-glucanotransferase) converts two molecules of maltotriose to a molecule of maltopentaose, which can now be acted on by the degradative enzymes, and one molecule of glucose that can be exported. We have determined the structure of the Arabidopsis plastidial DPE1 (AtDPE1), and, through ligand soaking experiments, we have trapped the enzyme in a variety of conformational states. AtDPE1 forms a homodimer with a deep, long, and open-ended active site canyon contained within each subunit. The canyon is divided into donor and acceptor sites with the catalytic residues at their junction; a number of loops around the active site adopt different conformations dependent on the occupancy of these sites. The "gate" is the most dynamic loop and appears to play a role in substrate capture, in particular in the binding of the acceptor molecule. Subtle changes in the configuration of the active site residues may prevent undesirable reactions or abortive hydrolysis of the covalently bound enzyme-substrate intermediate. Together, these observations allow us to delineate the complete AtDPE1 disproportionation cycle in structural terms.

Structural Dissection of the Maltodextrin Disproportionation Cycle of the Arabidopsis Plastidial Disproportionating Enzyme 1 (DPE1).,O'Neill EC, Stevenson CE, Tantanarat K, Latousakis D, Donaldson MI, Rejzek M, Nepogodiev SA, Limpaseni T, Field RA, Lawson DM J Biol Chem. 2015 Dec 11;290(50):29834-53. doi: 10.1074/jbc.M115.682245. Epub, 2015 Oct 26. PMID:26504082<ref>PMID:26504082</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 5csy" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Arabidopsis thaliana]]
[[Category: Large Structures]]
[[Category: Donaldson MI]]
[[Category: Field RA]]
[[Category: Latousakis D]]
[[Category: Lawson DM]]
[[Category: Limpaseni T]]
[[Category: O'Neill EC]]
[[Category: Rejzek M]]
[[Category: Smith AM]]
[[Category: Stevenson CEM]]
[[Category: Tantanarat K]]