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| | ==Crystal structure of 2-methylisoborneol synthase from Streptomyces coelicolor A3(2) in complex with Mg2+ and 2-fluoroneryl diphosphate== | | ==Crystal structure of 2-methylisoborneol synthase from Streptomyces coelicolor A3(2) in complex with Mg2+ and 2-fluoroneryl diphosphate== |
| - | <StructureSection load='4la6' size='340' side='right' caption='[[4la6]], [[Resolution|resolution]] 2.00Å' scene=''> | + | <StructureSection load='4la6' size='340' side='right'caption='[[4la6]], [[Resolution|resolution]] 2.00Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[4la6]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Strco Strco]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4LA6 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4LA6 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4la6]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_coelicolor_A3(2) Streptomyces coelicolor A3(2)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4LA6 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4LA6 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=LA6:(2E)-2-FLUORO-3,7-DIMETHYLOCTA-2,6-DIEN-1-YL+TRIHYDROGEN+DIPHOSPHATE'>LA6</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> | + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=LA6:(2E)-2-FLUORO-3,7-DIMETHYLOCTA-2,6-DIEN-1-YL+TRIHYDROGEN+DIPHOSPHATE'>LA6</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene></td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3v1v|3v1v]], [[3v1x|3v1x]], [[4la5|4la5]]</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=4la6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4la6 OCA], [https://pdbe.org/4la6 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4la6 RCSB], [https://www.ebi.ac.uk/pdbsum/4la6 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4la6 ProSAT]</span></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">SC1A4.08, SCBAC12C8.01, SCO7700 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=100226 STRCO])</td></tr>
| + | |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/2-methylisoborneol_synthase 2-methylisoborneol synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.3.118 4.2.3.118] </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=4la6 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4la6 OCA], [http://pdbe.org/4la6 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4la6 RCSB], [http://www.ebi.ac.uk/pdbsum/4la6 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4la6 ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/MIBS_STRCO MIBS_STRCO]] Catalyzes the cyclization of 2-methylgeranyl diphosphate (2-MeGPP) to 2-methylisoborneol (2-MIB), which likely involves the intermediacy of 2-methyllinalyl diphosphate. Is also able to catalyze the cyclization of geranyl diphosphate (GPP), albeit with much lower efficiency, leading to the formation of a complex mixture of cyclic monoterpenes, consisting of alpha-pinene (6%), beta-pinene (23%), limonene (32%), gamma-terpinene (29%), and delta-terpinene (10%). | + | [https://www.uniprot.org/uniprot/MIBS_STRCO MIBS_STRCO] Catalyzes the cyclization of 2-methylgeranyl diphosphate (2-MeGPP) to 2-methylisoborneol (2-MIB), which likely involves the intermediacy of 2-methyllinalyl diphosphate. Is also able to catalyze the cyclization of geranyl diphosphate (GPP), albeit with much lower efficiency, leading to the formation of a complex mixture of cyclic monoterpenes, consisting of alpha-pinene (6%), beta-pinene (23%), limonene (32%), gamma-terpinene (29%), and delta-terpinene (10%). |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: 2-methylisoborneol synthase]] | + | [[Category: Large Structures]] |
| - | [[Category: Strco]]
| + | [[Category: Christianson DW]] |
| - | [[Category: Christianson, D W]] | + | [[Category: Koksal M]] |
| - | [[Category: Koksal, M]] | + | |
| - | [[Category: Biosynthesis]]
| + | |
| - | [[Category: Isoprenoid synthase fold]]
| + | |
| - | [[Category: Lyase]]
| + | |
| - | [[Category: Terpenoid biosynthesis]]
| + | |
| Structural highlights
Function
MIBS_STRCO Catalyzes the cyclization of 2-methylgeranyl diphosphate (2-MeGPP) to 2-methylisoborneol (2-MIB), which likely involves the intermediacy of 2-methyllinalyl diphosphate. Is also able to catalyze the cyclization of geranyl diphosphate (GPP), albeit with much lower efficiency, leading to the formation of a complex mixture of cyclic monoterpenes, consisting of alpha-pinene (6%), beta-pinene (23%), limonene (32%), gamma-terpinene (29%), and delta-terpinene (10%).
Publication Abstract from PubMed
The crystal structure of 2-methylisoborneol synthase (MIBS) from Streptomyces coelicolor A3(2) has been determined in its unliganded state and in complex with two Mg2+ ions and 2-fluoroneryl diphosphate at 1.85 and 2.00 A resolution, respectively. Under normal circumstances, MIBS catalyzes the cyclization of the naturally occurring, noncanonical 11-carbon isoprenoid substrate, 2-methylgeranyl diphosphate, which first undergoes an ionization-isomerization-ionization sequence through the tertiary diphosphate intermediate 2-methyllinalyl diphosphate to enable subsequent cyclization chemistry. MIBS does not exhibit catalytic activity with 2-fluorogeranyl diphosphate, and we recently reported the crystal structure of MIBS complexed with this unreactive substrate analogue [ Koksal, M., Chou, W. K. W., Cane, D. E., Christianson, D. W. (2012) Biochemistry 51 , 3011-3020 ]. However, cocrystallization of MIBS with the fluorinated analogue of the tertiary allylic diphosphate intermediate, 2-fluorolinalyl diphosphate, reveals unexpected reactivity for the intermediate analogue and yields the crystal structure of the complex with the primary allylic diphosphate, 2-fluoroneryl diphosphate. Comparison with the structure of the unliganded enzyme reveals that the crystalline enzyme active site remains partially open, presumably due to the binding of only two Mg2+ ions. Assays in solution indicate that MIBS catalyzes the generation of (1R)-(+)-camphor from the substrate 2-fluorolinalyl diphosphate, suggesting that both 2-fluorolinalyl diphosphate and 2-methyllinalyl diphosphate follow the identical cyclization mechanism leading to 2-substituted isoborneol products; however, the initially generated 2-fluoroisoborneol cyclization product is unstable and undergoes elimination of hydrogen fluoride to yield (1R)-(+)-camphor.
Unexpected Reactivity of 2-Fluorolinalyl Diphosphate in the Active Site of Crystalline 2-Methylisoborneol Synthase.,Koksal M, Chou WK, Cane DE, Christianson DW Biochemistry. 2013 Jul 22. PMID:23844678[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Koksal M, Chou WK, Cane DE, Christianson DW. Unexpected Reactivity of 2-Fluorolinalyl Diphosphate in the Active Site of Crystalline 2-Methylisoborneol Synthase. Biochemistry. 2013 Jul 22. PMID:23844678 doi:10.1021/bi400797c
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