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| | ==Crystal structure of GltPh K55C-A364C mutant crosslinked with divalent mercury== | | ==Crystal structure of GltPh K55C-A364C mutant crosslinked with divalent mercury== |
| - | <StructureSection load='3kbc' size='340' side='right' caption='[[3kbc]], [[Resolution|resolution]] 3.51Å' scene=''> | + | <StructureSection load='3kbc' size='340' side='right'caption='[[3kbc]], [[Resolution|resolution]] 3.51Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3kbc]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/'pyrococcus_shinkaii' 'pyrococcus shinkaii']. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3KBC OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3KBC FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3kbc]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Pyrococcus_horikoshii Pyrococcus horikoshii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3KBC OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3KBC FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ASP:ASPARTIC+ACID'>ASP</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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]] 3.51Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2nwl|2nwl]], [[2nww|2nww]], [[2nwx|2nwx]], [[1xfh|1xfh]]</td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ASP:ASPARTIC+ACID'>ASP</scene>, <scene name='pdbligand=HG:MERCURY+(II)+ION'>HG</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=53953 'Pyrococcus shinkaii'])</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=3kbc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3kbc OCA], [https://pdbe.org/3kbc PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3kbc RCSB], [https://www.ebi.ac.uk/pdbsum/3kbc PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3kbc 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=3kbc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3kbc OCA], [http://pdbe.org/3kbc PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3kbc RCSB], [http://www.ebi.ac.uk/pdbsum/3kbc PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3kbc 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] |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Pyrococcus shinkaii]] | + | [[Category: Large Structures]] |
| - | [[Category: Boudker, O]] | + | [[Category: Pyrococcus horikoshii]] |
| - | [[Category: Ginter, C]] | + | [[Category: Boudker O]] |
| - | [[Category: Reyes, N]] | + | [[Category: Ginter C]] |
| - | [[Category: Amino acid transporter]]
| + | [[Category: Reyes N]] |
| - | [[Category: Aspartate transporter]]
| + | |
| - | [[Category: Cysteine cross-link]]
| + | |
| - | [[Category: Inward-facing]]
| + | |
| - | [[Category: Transmembrane transporter]]
| + | |
| - | [[Category: Transport protein]]
| + | |
| 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]
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 PubMed
Glutamate transporters are integral membrane proteins that catalyse a thermodynamically uphill uptake of the neurotransmitter glutamate from the synaptic cleft into the cytoplasm of glia and neuronal cells by harnessing the energy of pre-existing electrochemical gradients of ions. Crucial to the reaction is the conformational transition of the transporters between outward and inward facing states, in which the substrate binding sites are accessible from the extracellular space and the cytoplasm, respectively. Here we describe the crystal structure of a double cysteine mutant of a glutamate transporter homologue from Pyrococcus horikoshii, Glt(Ph), which is trapped in the inward facing state by cysteine crosslinking. Together with the previously determined crystal structures of Glt(Ph) in the outward facing state, the structure of the crosslinked mutant allows us to propose a molecular mechanism by which Glt(Ph) and, by analogy, mammalian glutamate transporters mediate sodium-coupled substrate uptake.
Transport mechanism of a bacterial homologue of glutamate transporters.,Reyes N, Ginter C, Boudker O Nature. 2009 Dec 17;462(7275):880-5. Epub 2009 Nov 18. PMID:19924125[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
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
- ↑ Reyes N, Ginter C, Boudker O. Transport mechanism of a bacterial homologue of glutamate transporters. Nature. 2009 Dec 17;462(7275):880-5. Epub 2009 Nov 18. PMID:19924125 doi:10.1038/nature08616
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