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| | <StructureSection load='5tqn' size='340' side='right'caption='[[5tqn]], [[Resolution|resolution]] 1.80Å' scene=''> | | <StructureSection load='5tqn' size='340' side='right'caption='[[5tqn]], [[Resolution|resolution]] 1.80Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[5tqn]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Glycine_hispida Glycine hispida]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5TQN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5TQN FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[5tqn]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Glycine_max Glycine max]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5TQN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5TQN FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene></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]] 1.8Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[5tqo|5tqo]], [[5tqp|5tqp]], [[5tr0|5tr0]]</td></tr>
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FE2:FE+(II)+ION'>FE2</scene></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">LOX1.1, LOX1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=3847 Glycine hispida])</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=5tqn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5tqn OCA], [https://pdbe.org/5tqn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5tqn RCSB], [https://www.ebi.ac.uk/pdbsum/5tqn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5tqn ProSAT]</span></td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Oxidoreductase Oxidoreductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.12 1.13.11.12] </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=5tqn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5tqn OCA], [http://pdbe.org/5tqn PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5tqn RCSB], [http://www.ebi.ac.uk/pdbsum/5tqn PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5tqn ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/LOX1_SOYBN LOX1_SOYBN]] Plant lipoxygenase may be involved in a number of diverse aspects of plant physiology including growth and development, pest resistance, and senescence or responses to wounding. With linoleate as substrate, L-1 shows a preference for carbon 13 as the site for hydroperoxidation (in contrast to L-2 and L-3, which utilize either carbon 9 or 13). At pH above 8.5, only (9Z,11E,13S)-13-hydroperoxyoctadeca-9,11-dienoate is produced, but as the pH decreases, the proportion of (9S)-hydroperoxide increases linearly until at pH 6.0 it represents about 25 % of the products.<ref>PMID:16157595</ref> | + | [https://www.uniprot.org/uniprot/LOX1_SOYBN LOX1_SOYBN] Plant lipoxygenase may be involved in a number of diverse aspects of plant physiology including growth and development, pest resistance, and senescence or responses to wounding. With linoleate as substrate, L-1 shows a preference for carbon 13 as the site for hydroperoxidation (in contrast to L-2 and L-3, which utilize either carbon 9 or 13). At pH above 8.5, only (9Z,11E,13S)-13-hydroperoxyoctadeca-9,11-dienoate is produced, but as the pH decreases, the proportion of (9S)-hydroperoxide increases linearly until at pH 6.0 it represents about 25 % of the products.<ref>PMID:16157595</ref> |
| | <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: Glycine hispida]] | + | [[Category: Glycine max]] |
| | [[Category: Large Structures]] | | [[Category: Large Structures]] |
| - | [[Category: Oxidoreductase]]
| + | [[Category: Fraser JS]] |
| - | [[Category: Fraser, J S]] | + | [[Category: Gee C]] |
| - | [[Category: Gee, C]] | + | [[Category: Poss EM]] |
| - | [[Category: Poss, E M]] | + | |
| - | [[Category: Hydrogen tunneling]]
| + | |
| - | [[Category: Lipoxygenase]]
| + | |
| Structural highlights
Function
LOX1_SOYBN Plant lipoxygenase may be involved in a number of diverse aspects of plant physiology including growth and development, pest resistance, and senescence or responses to wounding. With linoleate as substrate, L-1 shows a preference for carbon 13 as the site for hydroperoxidation (in contrast to L-2 and L-3, which utilize either carbon 9 or 13). At pH above 8.5, only (9Z,11E,13S)-13-hydroperoxyoctadeca-9,11-dienoate is produced, but as the pH decreases, the proportion of (9S)-hydroperoxide increases linearly until at pH 6.0 it represents about 25 % of the products.[1]
Publication Abstract from PubMed
Soybean lipoxygenase (SLO) has served as a prototype for understanding the molecular origin of enzymatic rate accelerations. The double mutant (DM) L546A/L754A is considered a dramatic outlier, due to the unprecedented size and near temperature-independence of its primary kinetic isotope effect, low catalytic efficiency, and elevated enthalpy of activation. To uncover the physical basis of these features, we herein apply three structural probes: hydrogen-deuterium exchange mass spectrometry, room-temperature X-ray crystallography and EPR spectroscopy on four SLO variants (wild-type (WT) enzyme, DM, and the two parental single mutants, L546A and L754A). DM is found to incorporate features of each parent, with the perturbation at position 546 predominantly influencing thermally activated motions that connect the active site to a protein-solvent interface, while mutation at position 754 disrupts the ligand field and solvation near the cofactor iron. However, the expanded active site in DM leads to more active site water molecules and their associated hydrogen bond network, and the individual features from L546A and L754A alone cannot explain the aggregate kinetic properties for DM. Using recently published QM/MM-derived ground-state SLO-substrate complexes for WT and DM, together with the thorough structural analyses presented herein, we propose that the impairment of DM is the combined result of a repositioning of the reactive carbon of linoleic acid substrate with regard to both the iron cofactor and a catalytically linked dynamic region of protein.
Biophysical Characterization of a Disabled Double Mutant of Soybean Lipoxygenase: The "Undoing" of Precise Substrate Positioning Relative to Metal Cofactor and an Identified Dynamical Network.,Hu S, Offenbacher AR, Thompson EM, Gee CL, Wilcoxen J, Carr CAM, Prigozhin DM, Yang V, Alber T, Britt RD, Fraser JS, Klinman JP J Am Chem Soc. 2019 Jan 30;141(4):1555-1567. doi: 10.1021/jacs.8b10992. Epub 2019, Jan 15. PMID:30645119[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Coffa G, Imber AN, Maguire BC, Laxmikanthan G, Schneider C, Gaffney BJ, Brash AR. On the relationships of substrate orientation, hydrogen abstraction, and product stereochemistry in single and double dioxygenations by soybean lipoxygenase-1 and its Ala542Gly mutant. J Biol Chem. 2005 Nov 18;280(46):38756-66. Epub 2005 Sep 12. PMID:16157595 doi:http://dx.doi.org/10.1074/jbc.M504870200
- ↑ Hu S, Offenbacher AR, Thompson EM, Gee CL, Wilcoxen J, Carr CAM, Prigozhin DM, Yang V, Alber T, Britt RD, Fraser JS, Klinman JP. Biophysical Characterization of a Disabled Double Mutant of Soybean Lipoxygenase: The "Undoing" of Precise Substrate Positioning Relative to Metal Cofactor and an Identified Dynamical Network. J Am Chem Soc. 2019 Jan 30;141(4):1555-1567. doi: 10.1021/jacs.8b10992. Epub 2019, Jan 15. PMID:30645119 doi:http://dx.doi.org/10.1021/jacs.8b10992
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