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| ==Crystal structure of Pseudomonas aeruginosa OprO== | | ==Crystal structure of Pseudomonas aeruginosa OprO== |
| <StructureSection load='4rjw' size='340' side='right' caption='[[4rjw]], [[Resolution|resolution]] 1.52Å' scene=''> | | <StructureSection load='4rjw' size='340' side='right'caption='[[4rjw]], [[Resolution|resolution]] 1.52Å' scene=''> |
| == Structural highlights == | | == Structural highlights == |
| <table><tr><td colspan='2'>[[4rjw]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4RJW OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4RJW FirstGlance]. <br> | | <table><tr><td colspan='2'>[[4rjw]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_aeruginosa_PAO1 Pseudomonas aeruginosa PAO1]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4RJW OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4RJW FirstGlance]. <br> |
| </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=C8E:(HYDROXYETHYLOXY)TRI(ETHYLOXY)OCTANE'>C8E</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]] 1.52Å</td></tr> |
| <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4rjx|4rjx]]</td></tr> | | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=C8E:(HYDROXYETHYLOXY)TRI(ETHYLOXY)OCTANE'>C8E</scene></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=4rjw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4rjw OCA], [http://pdbe.org/4rjw PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4rjw RCSB], [http://www.ebi.ac.uk/pdbsum/4rjw PDBsum]</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=4rjw FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4rjw OCA], [https://pdbe.org/4rjw PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4rjw RCSB], [https://www.ebi.ac.uk/pdbsum/4rjw PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4rjw ProSAT]</span></td></tr> |
| </table> | | </table> |
| == Function == | | == Function == |
| [[http://www.uniprot.org/uniprot/PORO_PSEAE PORO_PSEAE]] Anion specific, the binding site has higher affinity for phosphate than chloride ions. Porin O has a higher affinity for polyphosphates (tripolyphosphate and pyrophosphate) while porin P has a higher affinity for orthophosphate. | | [https://www.uniprot.org/uniprot/PORO_PSEAE PORO_PSEAE] Anion specific, the binding site has higher affinity for phosphate than chloride ions. Porin O has a higher affinity for polyphosphates (tripolyphosphate and pyrophosphate) while porin P has a higher affinity for orthophosphate. |
| <div style="background-color:#fffaf0;">
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| == Publication Abstract from PubMed ==
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| The outer membrane (OM) of Gram-negative bacteria functions as a selective permeability barrier between cell and environment. For nutrient acquisition, the OM contains a number of channels that mediate uptake of small molecules by diffusion. Many of these channels are specific, i.e., they prefer certain substrates over others. In electrophysiological experiments, the OM channels OprP and OprO from Pseudomonas aeruginosa show a specificity for phosphate and diphosphate, respectively. In this study we use x-ray crystallography, free-energy molecular dynamics (MD) simulations, and electrophysiology to uncover the atomic basis for the different substrate specificity of these highly similar channels. A structural analysis of OprP and OprO revealed two crucial differences in the central constriction region. In OprP there are two tyrosine residues, Y62 and Y114, whereas the corresponding residues in OprO are phenylalanine F62 and aspartate D114. To probe the importance of these two residues in generating the different substrate specificities, the double mutants were generated in silico and in vitro. Applied-field MD simulations and electrophysiological experiments demonstrated that the double mutations interchange the phosphate and diphosphate specificities of OprP and OprO. Our findings outline a possible strategy to rationally design channel specificity by modification of a small number of residues that may be applicable to other pores as well.
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| Structure, Dynamics, and Substrate Specificity of the OprO Porin from Pseudomonas aeruginosa.,Modi N, Ganguly S, Barcena-Uribarri I, Benz R, van den Berg B, Kleinekathofer U Biophys J. 2015 Oct 6;109(7):1429-38. doi: 10.1016/j.bpj.2015.07.035. PMID:26445443<ref>PMID:26445443</ref>
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| From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
| | ==See Also== |
| </div>
| | *[[Porin 3D structures|Porin 3D structures]] |
| <div class="pdbe-citations 4rjw" style="background-color:#fffaf0;"></div>
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| == References == | |
| <references/>
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| __TOC__ | | __TOC__ |
| </StructureSection> | | </StructureSection> |
| [[Category: Berg, B van den]] | | [[Category: Large Structures]] |
| [[Category: Beta-barrel]] | | [[Category: Pseudomonas aeruginosa PAO1]] |
| [[Category: Membrane protein]] | | [[Category: Van den Berg B]] |
| [[Category: Phosphate channel]]
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