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| - | [[Image:1hg0.gif|left|200px]]<br /><applet load="1hg0" size="350" color="white" frame="true" align="right" spinBox="true" | |
| - | caption="1hg0, resolution 1.90Å" /> | |
| - | '''X-RAY STRUCTURE OF THE COMPLEX BETWEEN ERWINIA CHRYSANTHEMI L-ASPARAGINASE AND SUCCINIC ACID'''<br /> | |
| | | | |
| - | ==Overview== | + | ==X-ray structure of the complex between Erwinia chrysanthemi L-asparaginase and succinic acid== |
| - | Bacterial L-asparaginases, enzymes that catalyze the hydrolysis of L-asparagine to aspartic acid, have been used for over 30 years as therapeutic agents in the treatment of acute childhood lymphoblastic leukemia. Other substrates of asparaginases include L-glutamine, D-asparagine, and succinic acid monoamide. In this report, we present high-resolution crystal structures of the complexes of Erwinia chrysanthemi L-asparaginase (ErA) with the products of such reactions that also can serve as substrates, namely L-glutamic acid (L-Glu), D-aspartic acid (D-Asp), and succinic acid (Suc). Comparison of the four independent active sites within each complex indicates unique and specific binding of the ligand molecules; the mode of binding is also similar between complexes. The lack of the alpha-NH3(+) group in Suc, compared to L-Asp, does not affect the binding mode. The side chain of L-Glu, larger than that of L-Asp, causes several structural distortions in the ErA active side. The active site flexible loop (residues 15-33) does not exhibit stable conformation, resulting in suboptimal orientation of the nucleophile, Thr15. Additionally, the delta-COO(-) plane of L-Glu is approximately perpendicular to the plane of gamma-COO(-) in L-Asp bound to the asparaginase active site. Binding of D-Asp to the ErA active site is very distinctive compared to the other ligands, suggesting that the low activity of ErA against D-Asp could be mainly attributed to the low k(cat) value. A comparison of the amino acid sequence and the crystal structure of ErA with those of other bacterial L-asparaginases shows that the presence of two active-site residues, Glu63(ErA) and Ser254(ErA), may correlate with significant glutaminase activity, while their substitution by Gln and Asn, respectively, may lead to minimal L-glutaminase activity.
| + | <StructureSection load='1hg0' size='340' side='right'caption='[[1hg0]], [[Resolution|resolution]] 1.90Å' scene=''> |
| | + | == Structural highlights == |
| | + | <table><tr><td colspan='2'>[[1hg0]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Dickeya_chrysanthemi Dickeya chrysanthemi]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HG0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1HG0 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]] 1.9Å</td></tr> |
| | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SIN:SUCCINIC+ACID'>SIN</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=1hg0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1hg0 OCA], [https://pdbe.org/1hg0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1hg0 RCSB], [https://www.ebi.ac.uk/pdbsum/1hg0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1hg0 ProSAT]</span></td></tr> |
| | + | </table> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/ASPG_DICCH ASPG_DICCH] |
| | + | == Evolutionary Conservation == |
| | + | [[Image:Consurf_key_small.gif|200px|right]] |
| | + | Check<jmol> |
| | + | <jmolCheckbox> |
| | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/hg/1hg0_consurf.spt"</scriptWhenChecked> |
| | + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| | + | <text>to colour the structure by Evolutionary Conservation</text> |
| | + | </jmolCheckbox> |
| | + | </jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1hg0 ConSurf]. |
| | + | <div style="clear:both"></div> |
| | | | |
| - | ==About this Structure== | + | ==See Also== |
| - | 1HG0 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Erwinia_chrysanthemi Erwinia chrysanthemi] with <scene name='pdbligand=SIN:'>SIN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Asparaginase Asparaginase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.1 3.5.1.1] Known structural/functional Sites: <scene name='pdbsite=AS1:Active+Site+Chain+A'>AS1</scene>, <scene name='pdbsite=AS2:Active+Site+Chain+B'>AS2</scene>, <scene name='pdbsite=AS3:Active+Site+Chain+C'>AS3</scene>, <scene name='pdbsite=AS4:Active+Site+Chain+D'>AS4</scene>, <scene name='pdbsite=LI1:Sin+Binding+Site+For+Chain+A'>LI1</scene>, <scene name='pdbsite=LI2:Sin+Binding+Site+For+Chain+B'>LI2</scene>, <scene name='pdbsite=LI3:Sin+Binding+Site+For+Chain+C'>LI3</scene> and <scene name='pdbsite=LI4:Sin+Binding+Site+For+Chain+D'>LI4</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HG0 OCA].
| + | *[[Asparaginase 3D structures|Asparaginase 3D structures]] |
| - | | + | __TOC__ |
| - | ==Reference==
| + | </StructureSection> |
| - | Structural basis for the activity and substrate specificity of Erwinia chrysanthemi L-asparaginase., Aghaiypour K, Wlodawer A, Lubkowski J, Biochemistry. 2001 May 15;40(19):5655-64. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=11341830 11341830]
| + | [[Category: Dickeya chrysanthemi]] |
| - | [[Category: Asparaginase]]
| + | [[Category: Large Structures]] |
| - | [[Category: Erwinia chrysanthemi]] | + | [[Category: Kolyani KA]] |
| - | [[Category: Single protein]] | + | [[Category: Lubkowski J]] |
| - | [[Category: Kolyani, K A.]] | + | [[Category: Wlodawer A]] |
| - | [[Category: Lubkowski, J.]] | + | |
| - | [[Category: Wlodawer, A.]] | + | |
| - | [[Category: SIN]]
| + | |
| - | [[Category: asparaginase]]
| + | |
| - | [[Category: complex]]
| + | |
| - | [[Category: d-aspartate]]
| + | |
| - | [[Category: hydrolase]]
| + | |
| - | [[Category: structure]]
| + | |
| - | [[Category: x-ray]]
| + | |
| - | | + | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:00:55 2008''
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