4qi1
From Proteopedia
(Difference between revisions)
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== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[4qi1]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Haloquadratum_walsbyi_DSM_16790 Haloquadratum walsbyi DSM 16790]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4QI1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4QI1 FirstGlance]. <br> | <table><tr><td colspan='2'>[[4qi1]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Haloquadratum_walsbyi_DSM_16790 Haloquadratum walsbyi DSM 16790]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4QI1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4QI1 FirstGlance]. <br> | ||
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MPG:[(Z)-OCTADEC-9-ENYL]+(2R)-2,3-BIS(OXIDANYL)PROPANOATE'>MPG</scene>, <scene name='pdbligand=RET:RETINAL'>RET</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]] 1.85Å</td></tr> |
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MPG:[(Z)-OCTADEC-9-ENYL]+(2R)-2,3-BIS(OXIDANYL)PROPANOATE'>MPG</scene>, <scene name='pdbligand=RET:RETINAL'>RET</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=4qi1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4qi1 OCA], [https://pdbe.org/4qi1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4qi1 RCSB], [https://www.ebi.ac.uk/pdbsum/4qi1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4qi1 ProSAT]</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=4qi1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4qi1 OCA], [https://pdbe.org/4qi1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4qi1 RCSB], [https://www.ebi.ac.uk/pdbsum/4qi1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4qi1 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[https://www.uniprot.org/uniprot/BACR1_HALWD BACR1_HALWD] Light-driven proton pump. The chromophore contains 78% all-trans- and 22% 13-cis-retinal in the dark and 90% all-trans- and 10% 13-cis-retinal upon illumination with >500 nm light.<ref>PMID:21135094</ref> <ref>PMID:22248212</ref> <ref>PMID:23720753</ref> | [https://www.uniprot.org/uniprot/BACR1_HALWD BACR1_HALWD] Light-driven proton pump. The chromophore contains 78% all-trans- and 22% 13-cis-retinal in the dark and 90% all-trans- and 10% 13-cis-retinal upon illumination with >500 nm light.<ref>PMID:21135094</ref> <ref>PMID:22248212</ref> <ref>PMID:23720753</ref> | ||
| - | <div style="background-color:#fffaf0;"> | ||
| - | == Publication Abstract from PubMed == | ||
| - | Retinal bound light-driven proton pumps are widespread in eukaryotic and prokaryotic organisms. Among these pumps, bacteriorhodopsin (BR) proteins cooperate with ATP synthase to convert captured solar energy into a biologically consumable form, ATP. In an acidic environment or when pumped-out protons accumulate in the extracellular region, the maximum absorbance of BR proteins shifts markedly to the longer wavelengths. These conditions affect the light-driven proton pumping functional exertion as well. In this study, wild-type crystal structure of a BR with optical stability under wide pH range from a square halophilic archaeon, Haloquadratum walsbyi (HwBR), was solved in two crystal forms. One crystal form, refined to 1.85 A resolution, contains a trimer in the asymmetric unit, whereas another contains an antiparallel dimer was refined at 2.58 A. HwBR could not be classified into any existing subgroup of archaeal BR proteins based on the protein sequence phylogenetic tree, and it showed unique absorption spectral stability when exposed to low pH values. All structures showed a unique hydrogen-bonding network between Arg(82) and Thr(201), linking the BC and FG loops to shield the retinal-binding pocket in the interior from the extracellular environment. This result was supported by R82E mutation that attenuated the optical stability. The negatively charged cytoplasmic side and the Arg(82)-Thr(201) hydrogen bond may play an important role in the proton translocation trend in HwBR under acidic conditions. Our findings have unveiled a strategy adopted by BR proteins to solidify their defenses against unfavorable environments and maintain their optical properties associated with proton pumping. | ||
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| - | Structural and Functional Studies of a Newly Grouped Haloquadratum walsbyi Bacteriorhodopsin Reveal the Acid-resistant Light-driven Proton Pumping Activity.,Hsu MF, Fu HY, Cai CJ, Yi HP, Yang CS, Wang AH J Biol Chem. 2015 Dec 4;290(49):29567-77. doi: 10.1074/jbc.M115.685065. Epub 2015, Oct 19. PMID:26483542<ref>PMID:26483542</ref> | ||
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| - | </div> | ||
| - | <div class="pdbe-citations 4qi1" style="background-color:#fffaf0;"></div> | ||
==See Also== | ==See Also== | ||
Current revision
Crystal structure of H. walsbyi bacteriorhodopsin
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