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| - | [[Image:2i6w.jpg|left|200px]] | |
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| - | <!--
| + | ==Crystal structure of the multidrug efflux transporter AcrB== |
| - | The line below this paragraph, containing "STRUCTURE_2i6w", creates the "Structure Box" on the page.
| + | <StructureSection load='2i6w' size='340' side='right'caption='[[2i6w]], [[Resolution|resolution]] 3.10Å' scene=''> |
| - | You may change the PDB parameter (which sets the PDB file loaded into the applet)
| + | == Structural highlights == |
| - | or the SCENE parameter (which sets the initial scene displayed when the page is loaded),
| + | <table><tr><td colspan='2'>[[2i6w]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_BL21(DE3) Escherichia coli BL21(DE3)]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2I6W OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2I6W FirstGlance]. <br> |
| - | or leave the SCENE parameter empty for the default display.
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 3.1Å</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=2i6w FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2i6w OCA], [https://pdbe.org/2i6w PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2i6w RCSB], [https://www.ebi.ac.uk/pdbsum/2i6w PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2i6w ProSAT]</span></td></tr> |
| - | {{STRUCTURE_2i6w| PDB=2i6w | SCENE= }}
| + | </table> |
| - | | + | == Function == |
| - | '''Crystal structure of the multidrug efflux transporter AcrB'''
| + | [https://www.uniprot.org/uniprot/ACRB_ECOLI ACRB_ECOLI] AcrAB is a drug efflux protein with a broad substrate specificity.<ref>PMID:16915237</ref> <ref>PMID:16946072</ref> <ref>PMID:17194213</ref> |
| - | | + | == Evolutionary Conservation == |
| - | | + | [[Image:Consurf_key_small.gif|200px|right]] |
| - | ==Overview== | + | Check<jmol> |
| - | Crystal structures of the bacterial multidrug transporter AcrB in R32 and C2 space groups showing both symmetric and asymmetric trimeric assemblies, respectively, supplemented with biochemical investigations, have provided most of the structural basis for a molecular level understanding of the protein structure and mechanisms for substrate uptake and translocation carried out by this 114-kDa inner membrane protein. They suggest that AcrB captures ligands primarily from the periplasm. Substrates can also enter the inner cavity of the transporter from the cytoplasm, but the exact mechanism of this remains undefined. Analysis of the amino acid sequences of AcrB and its homologs revealed the presence of conserved residues at the N-terminus including two phenylalanines which may be exposed to the cytoplasm. Any potential role that these conserved residues may play in function has not been addressed by existing biochemical or structural studies. Since phenylalanine residues elsewhere in the protein have been implicated in ligand binding, we explored the structure of this N-terminal region to investigate structural determinants near the cytoplasmic opening that may mediate drug uptake. Our structure of AcrB in R32 space group reveals an N-terminus loop, reducing the diameter of the central opening to approximately 15 A as opposed to the previously reported value of approximately 30 A for crystal structures in this space group with disordered N-terminus. Recent structures of the AcrB in C2 space group have revealed a helical conformation of this N-terminus but have not discussed its possible implications. We present the crystal structure of AcrB that reveals the structure of the N-terminus containing the conserved residues. We hope that the structural information provides a structural basis for others to design further biochemical investigation of the role of this portion of AcrB in mediating cytoplasmic ligand discrimination and uptake.
| + | <jmolCheckbox> |
| - | | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/i6/2i6w_consurf.spt"</scriptWhenChecked> |
| - | ==About this Structure== | + | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| - | 2I6W is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2I6W OCA].
| + | <text>to colour the structure by Evolutionary Conservation</text> |
| - | | + | </jmolCheckbox> |
| - | ==Reference== | + | </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=2i6w ConSurf]. |
| - | Crystal structure of the multidrug efflux transporter AcrB at 3.1A resolution reveals the N-terminal region with conserved amino acids., Das D, Xu QS, Lee JY, Ankoudinova I, Huang C, Lou Y, DeGiovanni A, Kim R, Kim SH, J Struct Biol. 2007 Jun;158(3):494-502. Epub 2006 Dec 24. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17275331 17275331]
| + | <div style="clear:both"></div> |
| - | [[Category: Escherichia coli]] | + | == References == |
| - | [[Category: Single protein]] | + | <references/> |
| - | [[Category: Das, D.]] | + | __TOC__ |
| - | [[Category: Kim, S H.]] | + | </StructureSection> |
| - | [[Category: Xu, Q S.]] | + | [[Category: Large Structures]] |
| - | [[Category: Acrb]] | + | [[Category: Das D]] |
| - | [[Category: Membrane protein]] | + | [[Category: Kim SH]] |
| - | [[Category: Multidrug efflux transporter]] | + | [[Category: Xu QS]] |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun May 4 07:09:14 2008''
| + | |
