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2fed

From Proteopedia

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Structure of the E203Q mutant of the Cl-/H+ exchanger CLC-ec1 from E.Coli

Structural highlights

2fed is a 6 chain structure with sequence from Escherichia coli and Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 3.317Å
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

CLCA_ECOLI Proton-coupled chloride transporter. Functions as antiport system and exchanges two chloride ions for 1 proton. Probably acts as an electrical shunt for an outwardly-directed proton pump that is linked to amino acid decarboxylation, as part of the extreme acid resistance (XAR) response.^[1] ^[2] ^[3] ^[4] ^[5]

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

CLC-ec1 is a prokaryotic CLC-type Cl(-)/H+ exchange transporter. Little is known about the mechanism of H+ coupling to Cl-. A critical glutamate residue, E148, was previously shown to be required for Cl(-)/H+ exchange by mediating proton transfer between the protein and the extracellular solution. To test whether an analogous H+ acceptor exists near the intracellular side of the protein, we performed a mutagenesis scan of inward-facing carboxyl-bearing residues and identified E203 as the unique residue whose neutralization abolishes H+ coupling to Cl- transport. Glutamate at this position is strictly conserved in all known CLCs of the transporter subclass, while valine is always found here in CLC channels. The x-ray crystal structure of the E203Q mutant is similar to that of the wild-type protein. Cl- transport rate in E203Q is inhibited at neutral pH, and the double mutant, E148A/E203Q, shows maximal Cl- transport, independent of pH, as does the single mutant E148A. The results argue that substrate exchange by CLC-ec1 involves two separate but partially overlapping permeation pathways, one for Cl- and one for H+. These pathways are congruent from the protein's extracellular surface to E148, and they diverge beyond this point toward the intracellular side. This picture demands a transport mechanism fundamentally different from familiar alternating-access schemes.

Separate ion pathways in a Cl-/H+ exchanger.,Accardi A, Walden M, Nguitragool W, Jayaram H, Williams C, Miller C J Gen Physiol. 2005 Dec;126(6):563-70. PMID:16316975^[6]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Iyer R, Iverson TM, Accardi A, Miller C. A biological role for prokaryotic ClC chloride channels. Nature. 2002 Oct 17;419(6908):715-8. PMID:12384697 doi:10.1038/nature01000
↑ Accardi A, Miller C. Secondary active transport mediated by a prokaryotic homologue of ClC Cl- channels. Nature. 2004 Feb 26;427(6977):803-7. PMID:14985752 doi:10.1038/nature02314
↑ Lobet S, Dutzler R. Ion-binding properties of the ClC chloride selectivity filter. EMBO J. 2006 Jan 11;25(1):24-33. Epub 2005 Dec 8. PMID:16341087
↑ Nguitragool W, Miller C. Uncoupling of a CLC Cl-/H+ exchange transporter by polyatomic anions. J Mol Biol. 2006 Sep 29;362(4):682-90. Epub 2006 Aug 14. PMID:16905147 doi:10.1016/j.jmb.2006.07.006
↑ Jayaram H, Accardi A, Wu F, Williams C, Miller C. Ion permeation through a Cl--selective channel designed from a CLC Cl-/H+ exchanger. Proc Natl Acad Sci U S A. 2008 Aug 12;105(32):11194-9. Epub 2008 Aug 4. PMID:18678918
↑ Accardi A, Walden M, Nguitragool W, Jayaram H, Williams C, Miller C. Separate ion pathways in a Cl-/H+ exchanger. J Gen Physiol. 2005 Dec;126(6):563-70. PMID:16316975 doi:10.1085/jgp.200509417

1 Structural highlights
2 Function
3 Evolutionary Conservation
4 Publication Abstract from PubMed
5 See Also
6 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/2fed"

@@ Line 1: / Line 1: @@
 ==Structure of the E203Q mutant of the Cl-/H+ exchanger CLC-ec1 from E.Coli==
-<StructureSection load='2fed' size='340' side='right' caption='[[2fed]], [[Resolution|resolution]] 3.32&Aring;' scene=''>
+<StructureSection load='2fed' size='340' side='right'caption='[[2fed]], [[Resolution|resolution]] 3.32&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[2fed]] is a 6 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FED OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2FED FirstGlance]. <br>
+<table><tr><td colspan='2'>[[2fed]] is a 6 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FED OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2FED FirstGlance]. <br>
-</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1ots|1ots]], [[2fec|2fec]], [[2fee|2fee]]</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]] 3.317&#8491;</td></tr>
-<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">clcA, eriC ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=562 Escherichia coli])</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=2fed FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2fed OCA], [https://pdbe.org/2fed PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2fed RCSB], [https://www.ebi.ac.uk/pdbsum/2fed PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2fed 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=2fed FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2fed OCA], [http://www.rcsb.org/pdb/explore.do?structureId=2fed RCSB], [http://www.ebi.ac.uk/pdbsum/2fed PDBsum]</span></td></tr>
 </table>
 == Function ==
-[[http://www.uniprot.org/uniprot/CLCA_ECOLI CLCA_ECOLI]] Proton-coupled chloride transporter. Functions as antiport system and exchanges two chloride ions for 1 proton. Probably acts as an electrical shunt for an outwardly-directed proton pump that is linked to amino acid decarboxylation, as part of the extreme acid resistance (XAR) response.<ref>PMID:12384697</ref> <ref>PMID:14985752</ref> <ref>PMID:16341087</ref> <ref>PMID:16905147</ref> <ref>PMID:18678918</ref>
+[https://www.uniprot.org/uniprot/CLCA_ECOLI CLCA_ECOLI] Proton-coupled chloride transporter. Functions as antiport system and exchanges two chloride ions for 1 proton. Probably acts as an electrical shunt for an outwardly-directed proton pump that is linked to amino acid decarboxylation, as part of the extreme acid resistance (XAR) response.<ref>PMID:12384697</ref> <ref>PMID:14985752</ref> <ref>PMID:16341087</ref> <ref>PMID:16905147</ref> <ref>PMID:18678918</ref>
 == 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/fe/2fed_consurf.spt"</scriptWhenChecked>
+    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/fe/2fed_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/chain_selection.php?pdb_ID=2ata ConSurf].
+</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=2fed ConSurf].
 <div style="clear:both"></div>
 <div style="background-color:#fffaf0;">
@@ Line 27: / Line 27: @@
 From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
 </div>
+<div class="pdbe-citations 2fed" style="background-color:#fffaf0;"></div>
 ==See Also==
-*[[Monoclonal Antibody|Monoclonal Antibody]]
+*[[Monoclonal Antibodies 3D structures|Monoclonal Antibodies 3D structures]]
 == References ==
 <references/>
@@ Line 36: / Line 37: @@
 [[Category: Escherichia coli]]
 [[Category: Homo sapiens]]
-[[Category: Accardi, A]]
+[[Category: Large Structures]]
-[[Category: Jayaram, H]]
+[[Category: Accardi A]]
-[[Category: Miller, C]]
+[[Category: Jayaram H]]
-[[Category: Nguitragool, W]]
+[[Category: Miller C]]
-[[Category: Walden, M P]]
+[[Category: Nguitragool W]]
-[[Category: Williams, C]]
+[[Category: Walden MP]]
-[[Category: Chloride/proton exchange transporter]]
+[[Category: Williams C]]
-[[Category: Clc-ec1]]
-[[Category: Clca_ecoli]]
-[[Category: Membrane protein]]
-[[Category: Proton transport]]

2fed

From Proteopedia

Current revision

Structure of the E203Q mutant of the Cl-/H+ exchanger CLC-ec1 from E.Coli

Structural highlights

Function

Evolutionary Conservation

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

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