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| | ==Tl+-bound inward-facing state (bound conformation) of the glutamate transporter homologue GltPh== | | ==Tl+-bound inward-facing state (bound conformation) of the glutamate transporter homologue GltPh== |
| - | <StructureSection load='4p6h' size='340' side='right' caption='[[4p6h]], [[Resolution|resolution]] 4.08Å' scene=''> | + | <StructureSection load='4p6h' size='340' side='right'caption='[[4p6h]], [[Resolution|resolution]] 4.08Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[4p6h]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Pyrococcus_horikoshii Pyrococcus horikoshii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4P6H OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4P6H FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4p6h]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Pyrococcus_horikoshii_OT3 Pyrococcus horikoshii OT3]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4P6H OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4P6H FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene>, <scene name='pdbligand=TL:THALLIUM+(I)+ION'>TL</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]] 4.08Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1xfh|1xfh]], [[2nwl|2nwl]], [[2nww|2nww]], [[2nwx|2nwx]], [[3kbc|3kbc]], [[3v8f|3v8f]], [[3v8g|3v8g]], [[4izm|4izm]]</td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene>, <scene name='pdbligand=TL:THALLIUM+(I)+ION'>TL</scene></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">PH1295 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=70601 Pyrococcus horikoshii])</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=4p6h FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4p6h OCA], [https://pdbe.org/4p6h PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4p6h RCSB], [https://www.ebi.ac.uk/pdbsum/4p6h PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4p6h ProSAT]</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=4p6h FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4p6h OCA], [http://pdbe.org/4p6h PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4p6h RCSB], [http://www.ebi.ac.uk/pdbsum/4p6h PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4p6h ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/GLT_PYRHO GLT_PYRHO] Sodium-dependent, high-affinity amino acid transporter that mediates aspartate uptake (PubMed:17435767, PubMed:19380583, PubMed:17230192, Ref.11). Has only very low glutamate transport activity (PubMed:19380583, PubMed:17230192). Functions as a symporter that transports one amino acid molecule together with two or three Na(+) ions, resulting in electrogenic transport (PubMed:17435767, PubMed:19380583, Ref.11). Na(+) binding enhances the affinity for aspartate (PubMed:19380583, Ref.11). Mediates Cl(-) flux that is not coupled to amino acid transport; this avoids the accumulation of negative charges due to aspartate and Na(+) symport (PubMed:17435767). In contrast to mammalian homologs, transport does not depend on pH or K(+) ions (PubMed:19380583).<ref>PMID:17230192</ref> <ref>PMID:17435767</ref> <ref>PMID:19380583</ref> [PDB:4P19] |
| | <div style="background-color:#fffaf0;"> | | <div style="background-color:#fffaf0;"> |
| | == Publication Abstract from PubMed == | | == Publication Abstract from PubMed == |
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| | </div> | | </div> |
| | <div class="pdbe-citations 4p6h" style="background-color:#fffaf0;"></div> | | <div class="pdbe-citations 4p6h" style="background-color:#fffaf0;"></div> |
| | + | |
| | + | ==See Also== |
| | + | *[[Symporter 3D structures|Symporter 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Pyrococcus horikoshii]] | + | [[Category: Large Structures]] |
| - | [[Category: Boudker, O]] | + | [[Category: Pyrococcus horikoshii OT3]] |
| - | [[Category: Verdon, G]] | + | [[Category: Boudker O]] |
| - | [[Category: Transport protein]] | + | [[Category: Verdon G]] |
| Structural highlights
Function
GLT_PYRHO Sodium-dependent, high-affinity amino acid transporter that mediates aspartate uptake (PubMed:17435767, PubMed:19380583, PubMed:17230192, Ref.11). Has only very low glutamate transport activity (PubMed:19380583, PubMed:17230192). Functions as a symporter that transports one amino acid molecule together with two or three Na(+) ions, resulting in electrogenic transport (PubMed:17435767, PubMed:19380583, Ref.11). Na(+) binding enhances the affinity for aspartate (PubMed:19380583, Ref.11). Mediates Cl(-) flux that is not coupled to amino acid transport; this avoids the accumulation of negative charges due to aspartate and Na(+) symport (PubMed:17435767). In contrast to mammalian homologs, transport does not depend on pH or K(+) ions (PubMed:19380583).[1] [2] [3] [PDB:4P19]
Publication Abstract from PubMed
Membrane transporters that clear the neurotransmitter glutamate from synapses are driven by symport of sodium ions and counter-transport of a potassium ion. Previous crystal structures of a homologous archaeal sodium and aspartate symporter showed that a dedicated transport domain carries the substrate and ions across the membrane. Here, we report new crystal structures of this homologue in ligand-free and ions-only bound outward- and inward-facing conformations. We show that after ligand release, the apo transport domain adopts a compact and occluded conformation that can traverse the membrane, completing the transport cycle. Sodium binding primes the transport domain to accept its substrate and triggers extracellular gate opening, which prevents inward domain translocation until substrate binding takes place. Furthermore, we describe a new cation-binding site ideally suited to bind a counter-transported ion. We suggest that potassium binding at this site stabilizes the translocation-competent conformation of the unloaded transport domain in mammalian homologues.
Coupled ion binding and structural transitions along the transport cycle of glutamate transporters.,Verdon G, Oh S, Serio RN, Boudker O Elife. 2014 May 19:e02283. doi: 10.7554/eLife.02283. PMID:24842876[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Boudker O, Ryan RM, Yernool D, Shimamoto K, Gouaux E. Coupling substrate and ion binding to extracellular gate of a sodium-dependent aspartate transporter. Nature. 2007 Jan 25;445(7126):387-93. Epub 2007 Jan 17. PMID:17230192 doi:10.1038/nature05455
- ↑ Ryan RM, Mindell JA. The uncoupled chloride conductance of a bacterial glutamate transporter homolog. Nat Struct Mol Biol. 2007 May;14(5):365-71. doi: 10.1038/nsmb1230. Epub 2007 Apr , 15. PMID:17435767 doi:http://dx.doi.org/10.1038/nsmb1230
- ↑ Ryan RM, Compton EL, Mindell JA. Functional characterization of a Na+-dependent aspartate transporter from Pyrococcus horikoshii. J Biol Chem. 2009 Jun 26;284(26):17540-8. doi: 10.1074/jbc.M109.005926. Epub 2009, Apr 20. PMID:19380583 doi:http://dx.doi.org/10.1074/jbc.M109.005926
- ↑ Verdon G, Oh S, Serio RN, Boudker O. Coupled ion binding and structural transitions along the transport cycle of glutamate transporters. Elife. 2014 May 19:e02283. doi: 10.7554/eLife.02283. PMID:24842876 doi:http://dx.doi.org/10.7554/eLife.02283
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