3dft: Difference between revisions
New page: '''Unreleased structure''' The entry 3dft is ON HOLD until Paper Publication Authors: St-Jean, M., Sygusch, J. Description: Phosphate ions in D33S mutant fructose-1,6-bisphosphate aldo... |
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==Phosphate ions in D33S mutant fructose-1,6-bisphosphate aldolase from rabbit muscle== | |||
<StructureSection load='3dft' size='340' side='right'caption='[[3dft]], [[Resolution|resolution]] 1.94Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[3dft]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3DFT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3DFT 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]] 1.94Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=3dft FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3dft OCA], [https://pdbe.org/3dft PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3dft RCSB], [https://www.ebi.ac.uk/pdbsum/3dft PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3dft ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/ALDOA_RABIT ALDOA_RABIT] Plays a key role in glycolysis and gluconeogenesis. In addition, may also function as scaffolding protein.<ref>PMID:17329259</ref> | |||
== 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/df/3dft_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=3dft ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Fructose-1,6-bisphosphate muscle aldolase is an essential glycolytic enzyme that catalyzes reversible carbon-carbon bond formation by cleaving fructose 1,6-bisphosphate to yield dihydroxyacetone phosphate (DHAP) and d-glyceraldehyde phosphate. To elucidate the mechanistic role of conserved amino acid Asp-33, Asn-33 and Ser-33 mutants were examined by kinetic and structural analyses. The mutations significantly compromised enzymatic activity and carbanion oxidation in presence of DHAP. Detailed structural analysis demonstrated that, like native crystals, Asp-33 mutant crystals, soaked in DHAP solutions, trapped Schiff base-derived intermediates covalently attached to Lys-229. The mutant structures, however, exhibited an abridged conformational change with the helical region (34-65) flanking the active site as well as pK(a) reductions and increased side chain disorder by central lysine residues, Lys-107 and Lys-146. These changes directly affect their interaction with the C-terminal Tyr-363, consistent with the absence of active site binding by the C-terminal region in the presence of phosphate. Lys-146 pK(a) reduction and side chain disorder would further compromise charge stabilization during C-C bond cleavage and proton transfer during enamine formation. These mechanistic impediments explain diminished catalytic activity and a reduced level of carbanion oxidation and are consistent with rate-determining proton transfer observed in the Asn-33 mutant. Asp-33 reduces the entropic cost and augments the enthalpic gain during catalysis by rigidifying Lys-107 and Lys-146, stabilizing their protonated forms, and promoting a conformational change triggered by substrate or obligate product binding, which lower kinetic barriers in C-C bond cleavage and Schiff base-enamine interconversion. | |||
Charge Stabilization and Entropy Reduction of Central Lysine Residues in Fructose-Bisphosphate Aldolase.,St-Jean M, Blonski C, Sygusch J Biochemistry. 2009 Apr 22. PMID:19354220<ref>PMID:19354220</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 3dft" style="background-color:#fffaf0;"></div> | |||
==See Also== | |||
*[[Aldolase 3D structures|Aldolase 3D structures]] | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Oryctolagus cuniculus]] | |||
[[Category: St-Jean M]] | |||
[[Category: Sygusch J]] | |||
Latest revision as of 15:46, 30 August 2023
Phosphate ions in D33S mutant fructose-1,6-bisphosphate aldolase from rabbit musclePhosphate ions in D33S mutant fructose-1,6-bisphosphate aldolase from rabbit muscle
Structural highlights
FunctionALDOA_RABIT Plays a key role in glycolysis and gluconeogenesis. In addition, may also function as scaffolding protein.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedFructose-1,6-bisphosphate muscle aldolase is an essential glycolytic enzyme that catalyzes reversible carbon-carbon bond formation by cleaving fructose 1,6-bisphosphate to yield dihydroxyacetone phosphate (DHAP) and d-glyceraldehyde phosphate. To elucidate the mechanistic role of conserved amino acid Asp-33, Asn-33 and Ser-33 mutants were examined by kinetic and structural analyses. The mutations significantly compromised enzymatic activity and carbanion oxidation in presence of DHAP. Detailed structural analysis demonstrated that, like native crystals, Asp-33 mutant crystals, soaked in DHAP solutions, trapped Schiff base-derived intermediates covalently attached to Lys-229. The mutant structures, however, exhibited an abridged conformational change with the helical region (34-65) flanking the active site as well as pK(a) reductions and increased side chain disorder by central lysine residues, Lys-107 and Lys-146. These changes directly affect their interaction with the C-terminal Tyr-363, consistent with the absence of active site binding by the C-terminal region in the presence of phosphate. Lys-146 pK(a) reduction and side chain disorder would further compromise charge stabilization during C-C bond cleavage and proton transfer during enamine formation. These mechanistic impediments explain diminished catalytic activity and a reduced level of carbanion oxidation and are consistent with rate-determining proton transfer observed in the Asn-33 mutant. Asp-33 reduces the entropic cost and augments the enthalpic gain during catalysis by rigidifying Lys-107 and Lys-146, stabilizing their protonated forms, and promoting a conformational change triggered by substrate or obligate product binding, which lower kinetic barriers in C-C bond cleavage and Schiff base-enamine interconversion. Charge Stabilization and Entropy Reduction of Central Lysine Residues in Fructose-Bisphosphate Aldolase.,St-Jean M, Blonski C, Sygusch J Biochemistry. 2009 Apr 22. PMID:19354220[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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