View source for 1yyt


==D100E Trichodiene Synthase: Complex With Mg, Pyrophosphate, and (4R)-7-azabisabolene==
<StructureSection load='1yyt' size='340' side='right'caption='[[1yyt]], [[Resolution|resolution]] 2.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1yyt]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Fusarium_sporotrichioides Fusarium sporotrichioides]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YYT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1YYT 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]] 2.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=POP:PYROPHOSPHATE+2-'>POP</scene>, <scene name='pdbligand=SAZ:(1S)-N,4-DIMETHYL-N-(4-METHYLPENT-3-ENYL)CYCLOHEX-3-ENAMINIUM'>SAZ</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=1yyt FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yyt OCA], [https://pdbe.org/1yyt PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1yyt RCSB], [https://www.ebi.ac.uk/pdbsum/1yyt PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1yyt ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/TRI5_FUSSP TRI5_FUSSP] TS is a member of the terpene cyclase group of enzymes. It catalyzes the isomerization and cyclization of farnesyl pyro-phosphate to form trichodiene, the first cyclic intermediate in the biosynthetic pathway for trichothecenes. It serves to branch trichothecene biosynthesis from the isoprenoid pathway.
== 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/yy/1yyt_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=1yyt ConSurf].
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== Publication Abstract from PubMed ==
The X-ray crystal structures of Y305F trichodiene synthase and its complex with coproduct inorganic pyrophosphate (PP(i)) and of Y305F and D100E trichodiene synthases in ternary complexes with PP(i) and aza analogues of the bisabolyl carbocation intermediate are reported. The Y305F substitution in the basic D(302)RRYR motif does not cause large changes in the overall structure in comparison with the wild-type enzyme in either the uncomplexed enzyme or its complex with PP(i). However, the loss of the Y305F-PP(i) hydrogen bond appears to be compensated by a very slight shift in the position of the side chain of R304. The putative bisabolyl carbocation mimic, R-azabisabolene, binds in a conformation and orientation that does not appear to mimic that of the actual carbocation intermediate, suggesting that the avid inhibition by R- and S-azabisabolenes arises more from favorable electrostatic interactions with PP(i) rather than any special resemblance to a reaction intermediate. Greater enclosed active-site volumes result from the Y305F and D100E mutations that appear to confer greater variability in ligand-binding conformations and orientations, which results in the formation of aberrant cyclization products. Because the binding conformations and orientations of R-azabisabolene to Y305F and D100E trichodiene synthases do not correspond to binding conformations required for product formation and because the binding conformations and orientations of diverse substrate and carbocation analogues to other cyclases such as 5-epi-aristolochene synthase and bornyl diphosphate synthase generally do not correspond to catalytically productive complexes, we conclude that the formation of transient carbocation intermediates in terpene cyclization reactions is generally under kinetic rather than thermodynamic control.

Molecular recognition of the substrate diphosphate group governs product diversity in trichodiene synthase mutants.,Vedula LS, Rynkiewicz MJ, Pyun HJ, Coates RM, Cane DE, Christianson DW Biochemistry. 2005 Apr 26;44(16):6153-63. PMID:15835903<ref>PMID:15835903</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1yyt" style="background-color:#fffaf0;"></div>

==See Also==
*[[Trichodiene synthase|Trichodiene synthase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Fusarium sporotrichioides]]
[[Category: Large Structures]]
[[Category: Cane DE]]
[[Category: Christianson DW]]
[[Category: Coates RM]]
[[Category: Pyun HJ]]
[[Category: Rynkiewicz MJ]]
[[Category: Vedula LS]]