1a5a: Difference between revisions

← Older edit

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA

@@ Line 1: / Line 1: @@
-[[Image:1a5a.gif|left|200px]]<br /><applet load="1a5a" size="350" color="white" frame="true" align="right" spinBox="true"
-caption="1a5a, resolution 1.9&Aring;" />
-'''CRYO-CRYSTALLOGRAPHY OF A TRUE SUBSTRATE, INDOLE-3-GLYCEROL PHOSPHATE, BOUND TO A MUTANT (ALPHAD60N) TRYPTOPHAN SYNTHASE ALPHA2BETA2 COMPLEX REVEALS THE CORRECT ORIENTATION OF ACTIVE SITE ALPHA GLU 49'''<br />
-==Overview==
+==CRYO-CRYSTALLOGRAPHY OF A TRUE SUBSTRATE, INDOLE-3-GLYCEROL PHOSPHATE, BOUND TO A MUTANT (ALPHAD60N) TRYPTOPHAN SYNTHASE ALPHA2BETA2 COMPLEX REVEALS THE CORRECT ORIENTATION OF ACTIVE SITE ALPHA GLU 49==
-The reversible cleavage of indole-3-glycerol by the alpha-subunit of, tryptophan synthase has been proposed to be catalyzed by alphaGlu49 and, alphaAsp60. Although previous x-ray crystallographic structures of the, tryptophan synthase alpha2beta2 complex showed an interaction between the, carboxylate of alphaAsp60 and the bound inhibitor indole-3-propanol, phosphate, the carboxylate of alphaGlu49 was too distant to play its, proposed role. To clarify the structural and functional roles of, alphaGlu49, we have determined crystal structures of a mutant (alphaD60N), alpha2beta2 complex in the presence and absence of the true substrate, indole-3-glycerol phosphate. The enzyme in the crystal cleaves, indole-3-glycerol phosphate very slowly at room temperature but not under, cryo-conditions of 95 K. The structure of the complex with the true, substrate obtained by cryo-crystallography reveals that indole-3-glycerol, phosphate and indole-3-propanol phosphate have similar binding modes but, different torsion angles. Most importantly, the side chain of alphaGlu49, interacts with 3-hydroxyl group of indole-3-glycerol phosphate as, proposed. The movement of the side chain of alphaGlu49 into an extended, conformation upon binding the true substrate provides evidence for an, induced fit mechanism. Our results demonstrate how cryo-crystallography, and mutagenesis can provide insight into enzyme mechanism.
+<StructureSection load='1a5a' size='340' side='right'caption='[[1a5a]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
+== Structural highlights ==
+<table><tr><td colspan='2'>[[1a5a]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Salmonella_enterica_subsp._enterica_serovar_Typhimurium Salmonella enterica subsp. enterica serovar Typhimurium]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A5A OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1A5A 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=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=PLP:PYRIDOXAL-5-PHOSPHATE'>PLP</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=1a5a FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1a5a OCA], [https://pdbe.org/1a5a PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1a5a RCSB], [https://www.ebi.ac.uk/pdbsum/1a5a PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1a5a ProSAT]</span></td></tr>
+</table>
+== Function ==
+[https://www.uniprot.org/uniprot/TRPA_SALTY TRPA_SALTY] The alpha subunit is responsible for the aldol cleavage of indoleglycerol phosphate to indole and glyceraldehyde 3-phosphate.
+== 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/a5/1a5a_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=1a5a ConSurf].
+<div style="clear:both"></div>
-==About this Structure==
+==See Also==
-A5A is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Salmonella_typhimurium Salmonella typhimurium] with <scene name='pdbligand=K:'>K</scene> and <scene name='pdbligand=PLP:'>PLP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Tryptophan_synthase Tryptophan synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.20 4.2.1.20] Known structural/functional Site: <scene name='pdbsite=PLP:Coenzyme+Plp+Binding+Site'>PLP</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A5A OCA].
+*[[Tryptophan synthase 3D structures|Tryptophan synthase 3D structures]]
+__TOC__
-==Reference==
+</StructureSection>
-Cryo-crystallography of a true substrate, indole-3-glycerol phosphate, bound to a mutant (alphaD60N) tryptophan synthase alpha2beta2 complex reveals the correct orientation of active site alphaGlu49., Rhee S, Miles EW, Davies DR, J Biol Chem. 1998 Apr 10;273(15):8553-5. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=9535826 9535826]
+[[Category: Large Structures]]
-[[Category: Protein complex]]
+[[Category: Salmonella enterica subsp. enterica serovar Typhimurium]]
-[[Category: Salmonella typhimurium]]
+[[Category: Davies DR]]
-[[Category: Tryptophan synthase]]
+[[Category: Miles EW]]
-[[Category: Davies, D.R.]]
+[[Category: Rhee S]]
-[[Category: Miles, E.W.]]
-[[Category: Rhee, S.]]
-[[Category: K]]
-[[Category: PLP]]
-[[Category: carbon-oxygen lyase]]
-[[Category: mutation at position 60 (asp --> asn) in the a-subunit]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Feb  3 09:29:08 2008''