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| [[Image:1beu.gif|left|200px]]<br />
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| <applet load="1beu" size="450" color="white" frame="true" align="right" spinBox="true"
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| caption="1beu, resolution 1.9Å" />
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| '''TRP SYNTHASE (D60N-IPP-SER) WITH K+'''<br />
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| ==Overview== | | ==TRP SYNTHASE (D60N-IPP-SER) WITH K+== |
| We have investigated the role of Asp60 of the alpha-subunit in allosteric, communication between the tryptophan synthase alpha- and beta-subunits., Crystallographic and microspectrophotometric studies have been carried out, on a mutant (alpha D60N) tryptophan synthase alpha 2 beta 2 complex which, has no observable alpha-activity, but has substantial beta-activity., Single-crystal polarized absorption spectra indicate that the external, aldimine is the predominant L-serine intermediate and that the amount of, the intermediate formed is independent of pH, monovalent cations, and, allosteric effectors. The three-dimensional structure is reported for this, mutant enzyme complexed with indole 3-propanol phosphate bound to the, alpha-site and L-serine bound to the beta-site (alpha D60N-IPP-Ser), and, this structure is compared with that of the unliganded mutant enzyme, (alpha D60N). In the complex, L-serine forms a stable external aldimine, with the pyridoxal phosphate coenzyme at the active site of the, beta-subunit. The conformation of the unliganded mutant is almost, identical to that of the wild type enzyme. However, the structure of the, mutant complexed with IPP and serine exhibits ligand-induced, conformational changes much smaller than those observed previously for, another mutant enzyme in the presence of the same ligands (beta, K87T-IPP-Ser) [Rhee, S., Parris, K. D., Hyde, C. C., Ahmed, S. A., Miles, E. W., and Davies, D. R. (1997) Biochemistry 36, 7664-7680]. The alpha, D60N-IPP-Ser alpha 2 beta 2 complex does not undergo the following, ligand-induced conformational changes: (1) the closure of the, alpha-subunit loop 6 (residues 178-191), (2) the movement of the mobile, subdomain (residues 93-189) of the beta-subunit, and (3) the rotation of, the alpha-subunit relative to the beta-subunit. These observations show, that alpha Asp60 plays important roles in the closure of loop 6 and in, allosteric communication between the alpha- and beta-subunits.
| | <StructureSection load='1beu' size='340' side='right'caption='[[1beu]], [[Resolution|resolution]] 1.90Å' scene=''> |
| | == Structural highlights == |
| | <table><tr><td colspan='2'>[[1beu]] 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=1BEU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1BEU 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=IPL:INDOLE-3-PROPANOL+PHOSPHATE'>IPL</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=PLS:[3-HYDROXY-2-METHYL-5-PHOSPHONOOXYMETHYL-PYRIDIN-4-YLMETHYL]-SERINE'>PLS</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=1beu FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1beu OCA], [https://pdbe.org/1beu PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1beu RCSB], [https://www.ebi.ac.uk/pdbsum/1beu PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1beu 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/be/1beu_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=1beu ConSurf]. |
| | <div style="clear:both"></div> |
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| ==About this Structure== | | ==See Also== |
| 1BEU 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 K, IPL and PLS 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] Structure known Active Sites: NUA and NUB. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1BEU OCA].
| | *[[Tryptophan synthase 3D structures|Tryptophan synthase 3D structures]] |
| | | __TOC__ |
| ==Reference==
| | </StructureSection> |
| Cryocrystallography and microspectrophotometry of a mutant (alpha D60N) tryptophan synthase alpha 2 beta 2 complex reveals allosteric roles of alpha Asp60., Rhee S, Miles EW, Mozzarelli A, Davies DR, Biochemistry. 1998 Jul 28;37(30):10653-9. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=9692955 9692955]
| | [[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: Mozzarelli A]] |
| [[Category: Miles, E.W.]] | | [[Category: Rhee S]] |
| [[Category: Mozzarelli, A.]] | |
| [[Category: Rhee, S.]] | |
| [[Category: IPL]]
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| [[Category: K]]
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| [[Category: PLS]]
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| [[Category: carbon-oxygen lyase]]
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| [[Category: indole-3-propanol phosphate in a-subunit]]
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| [[Category: l-serine in b-subunit]]
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| [[Category: mutation d60n in a-subunit]]
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| ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:54:10 2007''
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