This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
5nil
From Proteopedia
(Difference between revisions)
m (Protected "5nil" [edit=sysop:move=sysop]) |
|||
| Line 1: | Line 1: | ||
| - | '''Unreleased structure''' | ||
| - | + | ==Structure of the MacAB-TolC ABC-type tripartite multidrug efflux pump-MacB section== | |
| + | <StructureSection load='5nil' size='340' side='right' caption='[[5nil]], [[Resolution|resolution]] 5.30Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[5nil]] is a 11 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5NIL OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5NIL FirstGlance]. <br> | ||
| + | </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=5nil FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5nil OCA], [http://pdbe.org/5nil PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5nil RCSB], [http://www.ebi.ac.uk/pdbsum/5nil PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5nil ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [[http://www.uniprot.org/uniprot/TOLC_ECOLI TOLC_ECOLI]] Outer membrane channel, which is required for the function of several efflux systems such as AcrAB-TolC, AcrEF-TolC, EmrAB-TolC and MacAB-TolC. These systems are involved in export of antibiotics and other toxic compounds from the cell. TolC is also involved in import of colicin E1 into the cells.<ref>PMID:6337123</ref> <ref>PMID:11274125</ref> <ref>PMID:15228545</ref> <ref>PMID:18955484</ref> <ref>PMID:23176499</ref> [[http://www.uniprot.org/uniprot/MACB_ECOLI MACB_ECOLI]] Part of the tripartite efflux system MacAB-TolC. MacB is a non-canonical ABC transporter that contains transmembrane domains (TMD), which form a pore in the inner membrane, and an ATP-binding domain (NBD), which is responsible for energy generation. When overexpressed, the system confers resistance against macrolides composed of 14- and 15-membered lactones but no or weak resistance against 16-membered ones. In addition, the system could also transport R-LPS or a similar glycolipid.<ref>PMID:11544226</ref> <ref>PMID:17214741</ref> <ref>PMID:18955484</ref> <ref>PMID:23974027</ref> [[http://www.uniprot.org/uniprot/MACA_ECOLI MACA_ECOLI]] Part of the tripartite efflux system MacAB-TolC. MacA stimulates the ATPase activity of MacB by promoting the closed ATP-bound state of MacB, increases the capacity of MacB to bind macrolides such as erythromycin, and provides a physical link between MacB and TolC. When overexpressed, the system confers resistance against macrolides composed of 14- and 15-membered lactones but no or weak resistance against 16-membered ones. In addition, MacA binds tightly rough-core lipopolysaccharide (R-LPS), suggesting that the system could also transport R-LPS or a similar glycolipid.<ref>PMID:11544226</ref> <ref>PMID:17214741</ref> <ref>PMID:18955484</ref> <ref>PMID:21696464</ref> <ref>PMID:23974027</ref> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism. | ||
| - | + | Structure of the MacAB-TolC ABC-type tripartite multidrug efflux pump.,Fitzpatrick AWP, Llabres S, Neuberger A, Blaza JN, Bai XC, Okada U, Murakami S, van Veen HW, Zachariae U, Scheres SHW, Luisi BF, Du D Nat Microbiol. 2017 May 15;2:17070. doi: 10.1038/nmicrobiol.2017.70. PMID:28504659<ref>PMID:28504659</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 5nil" style="background-color:#fffaf0;"></div> | |
| - | + | == References == | |
| - | + | <references/> | |
| - | [[Category: | + | __TOC__ |
| - | [[Category: | + | </StructureSection> |
| + | [[Category: Bai, X C]] | ||
| + | [[Category: Blaza, J N]] | ||
[[Category: Du, D]] | [[Category: Du, D]] | ||
| - | [[Category: | + | [[Category: Fitzpatrick, A W.P]] |
| - | [[Category: | + | [[Category: Llabres, S]] |
| - | [[Category: | + | [[Category: Luisi, B F]] |
| - | [[Category: | + | [[Category: Murakami, S]] |
| - | + | ||
[[Category: Neuberger, A]] | [[Category: Neuberger, A]] | ||
| + | [[Category: Okada, U]] | ||
| + | [[Category: Scheres, S H.W]] | ||
| + | [[Category: Veen, H W.van]] | ||
| + | [[Category: Zachariae, U]] | ||
| + | [[Category: Abc transporter]] | ||
| + | [[Category: Drug efflux pump]] | ||
| + | [[Category: Macrolide transporter]] | ||
| + | [[Category: Multi-drug resistance]] | ||
| + | [[Category: Toxin transporter]] | ||
| + | [[Category: Transport protein]] | ||
Revision as of 13:40, 24 May 2017
Structure of the MacAB-TolC ABC-type tripartite multidrug efflux pump-MacB section
| |||||||||||
Categories: Bai, X C | Blaza, J N | Du, D | Fitzpatrick, A W.P | Llabres, S | Luisi, B F | Murakami, S | Neuberger, A | Okada, U | Scheres, S H.W | Veen, H W.van | Zachariae, U | Abc transporter | Drug efflux pump | Macrolide transporter | Multi-drug resistance | Toxin transporter | Transport protein
