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| [[Image:1e4b.gif|left|200px]]<br />
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| <applet load="1e4b" size="450" color="white" frame="true" align="right" spinBox="true"
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| caption="1e4b, resolution 1.84Å" />
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| '''L-FUCULOSE 1-PHOSPHATE ALDOLASE FROM ESCHERICHIA COLI MUTANT N29Q'''<br />
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| ==Overview== | | ==L-Fuculose 1-Phosphate Aldolase from Escherichia coli Mutant N29Q== |
| The crystal structures of l-fuculose-1-phosphate aldolase (FucA) with and, without a ligated analogue of dihydroxyacetone phosphate (DHAP) and of a, number of active center mutants have resulted in a model of the catalytic, mechanism. This model has now been confirmed by structural analyses of, further mutations at the zinc coordination sphere and at the phosphate, site. In addition, these mutants have revealed new aspects of the, catalysis: the hydroxyl group of Tyr113' (from a neighboring subunit), which sits just outside the zinc coordination sphere, steers DHAP towards, a productive binding mode at the zinc ion; Glu73 contacts zinc in between, the two ligand positions intended for the DHAP oxygen atoms and thus, avoids blocking of these positions by a tetrahedrally coordinated hydroxy, ion; the FucA polypeptide does not assume its minimum energy state but, oscillates between two states of elevated energy as demonstrated by a, mutant in a minimum energy state. The back and forth motion involves a, mobile loop connecting the phosphate site with intersubunit motions and, thus with the Brownian motion of the solvent. The phosphate group is bound, strongly at a given distance to the zinc ion, which prevents the formation, of too tight a DHAP:zinc complex. This observation explains our failure to, find mutants that accept phosphate-free substitutes for DHAP. The FucA, zinc coordination sphere is compared with that of carbonic anhydrase.
| | <StructureSection load='1e4b' size='340' side='right'caption='[[1e4b]], [[Resolution|resolution]] 1.84Å' scene=''> |
| | == Structural highlights == |
| | <table><tr><td colspan='2'>[[1e4b]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1E4B OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1E4B 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]] 1.84Å</td></tr> |
| | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=1e4b FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1e4b OCA], [https://pdbe.org/1e4b PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1e4b RCSB], [https://www.ebi.ac.uk/pdbsum/1e4b PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1e4b ProSAT]</span></td></tr> |
| | </table> |
| | == Function == |
| | [https://www.uniprot.org/uniprot/FUCA_ECOLI FUCA_ECOLI] |
| | == 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/e4/1e4b_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=1e4b ConSurf]. |
| | <div style="clear:both"></div> |
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| ==About this Structure== | | ==See Also== |
| 1E4B is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with SO4, ZN and BME as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/L-fuculose-phosphate_aldolase L-fuculose-phosphate aldolase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.2.17 4.1.2.17] Structure known Active Sites: ACT and MUT. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1E4B OCA].
| | *[[Aldolase 3D structures|Aldolase 3D structures]] |
| | | __TOC__ |
| ==Reference==
| | </StructureSection> |
| Structures of l-fuculose-1-phosphate aldolase mutants outlining motions during catalysis., Joerger AC, Mueller-Dieckmann C, Schulz GE, J Mol Biol. 2000 Nov 3;303(4):531-43. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=11054289 11054289]
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| [[Category: Escherichia coli]] | | [[Category: Escherichia coli]] |
| [[Category: L-fuculose-phosphate aldolase]] | | [[Category: Large Structures]] |
| [[Category: Single protein]]
| | [[Category: Joerger AC]] |
| [[Category: Joerger, A.C.]] | | [[Category: Schulz GE]] |
| [[Category: Schulz, G.E.]] | |
| [[Category: BME]]
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| [[Category: SO4]]
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| [[Category: ZN]]
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| [[Category: aldolase (class ii)]]
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| [[Category: bacterial l-fucose metabolism]]
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| [[Category: cleavage of l-fuculose-1-phosphate to dihydroxyacetone phosphate and l-lactaldehyde]]
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| [[Category: mutant structure]]
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| ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 12:23:53 2007''
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