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| | ==Crystal Structure of an alpha-Bisabolol synthase== | | ==Crystal Structure of an alpha-Bisabolol synthase== |
| - | <StructureSection load='4fjq' size='340' side='right' caption='[[4fjq]], [[Resolution|resolution]] 2.00Å' scene=''> | + | <StructureSection load='4fjq' size='340' side='right'caption='[[4fjq]], [[Resolution|resolution]] 2.00Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[4fjq]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Artemisia_annua Artemisia annua]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4FJQ OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4FJQ FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4fjq]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Artemisia_annua Artemisia annua]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4FJQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4FJQ FirstGlance]. <br> |
| - | </td></tr><tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">AaBOS, AMS1, KCS12 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=35608 Artemisia annua])</td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.0001Å</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Amorpha-4,11-diene_synthase Amorpha-4,11-diene synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.3.24 4.2.3.24] </span></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=4fjq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4fjq OCA], [https://pdbe.org/4fjq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4fjq RCSB], [https://www.ebi.ac.uk/pdbsum/4fjq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4fjq ProSAT]</span></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4fjq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4fjq OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4fjq RCSB], [http://www.ebi.ac.uk/pdbsum/4fjq PDBsum]</span></td></tr> | + | |
| | </table> | | </table> |
| - | <div style="background-color:#fffaf0;">
| + | == Function == |
| - | == Publication Abstract from PubMed == | + | [https://www.uniprot.org/uniprot/M4GGS0_ARTAN M4GGS0_ARTAN] |
| - | Most terpene synthases (TPSs) contain plasticity residues that are responsible for diversified terpene products and functional evolution, which provide a potential for improving catalytic efficiency. Artemisinin, a sesquiterpene lactone from Artemisia annua L., is widely used for malaria treatment and progress has been made in engineering the production of artemisinin or its precursors. Here, we report a new sesquiterpene synthase from A. annua, alpha-bisabolol synthase (AaBOS), which has high sequence identity to amorpha-4,11-diene synthase (AaADS), a key enzyme in artemisinin biosynthesis. Comparative analysis of the two enzymes by domain-swapping and structure-based mutagenesis led to the identification of several plasticity residues, whose alteration changed the product profile of AaBOS to include gamma-humulene as the major product. To elucidate the underlying mechanisms, we solved the crystal structures of AaBOS and a gamma-humulene-producing AaBOS mutant (AaBOS-M2). Among the plasticity residues, position 399, located in the substrate binding pocket, is crucial for both enzymes. In AaBOS, substitution of Leu with Thr (AaBOSL339T) is required for gamma-humulene production; whereas in AaADS, replacing the Thr with Ser (AaADST399S) resulted in a substantial increase of the activity of amorpha-4,11-diene production, likely as a result of accelerated product release. Our work demonstrates that substitution of plasticity residues holds a potential for improving catalytic efficiency of the enzyme.
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| - | Rational engineering plasticity residues of sesquiterpene synthases from Artemisia annua: product specificity and catalytic efficiency.,Li JX, Fang X, Zhao Q, Ruan JX, Yang CQ, Wang LJ, Miller DJ, Faraldos JA, Allemann RK, Chen XY, Zhang P Biochem J. 2013 Feb 26. PMID:23438177<ref>PMID:23438177</ref>
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| - | </div>
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| - | == References ==
| + | |
| - | <references/>
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Amorpha-4,11-diene synthase]] | |
| | [[Category: Artemisia annua]] | | [[Category: Artemisia annua]] |
| - | [[Category: Jianxu, L]] | + | [[Category: Large Structures]] |
| - | [[Category: Peng, Z]] | + | [[Category: Jianxu L]] |
| - | [[Category: Lyase]] | + | [[Category: Peng Z]] |
| - | [[Category: Sesquiterpene synthase]]
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