5A40

Crystal structure of a dual topology fluoride ion channel.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.60 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.235 
  • R-Value Observed: 0.236 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal Structures of a Double-Barrelled Fluoride Ion Channel.

Stockbridge, R.B.Kolmakova-Partensky, L.Shane, T.Koide, A.Koide, S.Miller, C.Newstead, S.

(2015) Nature 525: 548

  • DOI: 10.1038/nature14981
  • Primary Citation of Related Structures:  
    5A40, 5A43, 5NKQ

  • PubMed Abstract: 
  • To contend with hazards posed by environmental fluoride, microorganisms export this anion through F(-)-specific ion channels of the Fluc family. Since the recent discovery of Fluc channels, numerous idiosyncratic features of these proteins have been unearthed, including strong selectivity for F(-) over Cl(-) and dual-topology dimeric assembly ...

    To contend with hazards posed by environmental fluoride, microorganisms export this anion through F(-)-specific ion channels of the Fluc family. Since the recent discovery of Fluc channels, numerous idiosyncratic features of these proteins have been unearthed, including strong selectivity for F(-) over Cl(-) and dual-topology dimeric assembly. To understand the chemical basis for F(-) permeation and how the antiparallel subunits convene to form a F(-)-selective pore, here we solve the crystal structures of two bacterial Fluc homologues in complex with three different monobody inhibitors, with and without F(-) present, to a maximum resolution of 2.1 Å. The structures reveal a surprising 'double-barrelled' channel architecture in which two F(-) ion pathways span the membrane, and the dual-topology arrangement includes a centrally coordinated cation, most likely Na(+). F(-) selectivity is proposed to arise from the very narrow pores and an unusual anion coordination that exploits the quadrupolar edges of conserved phenylalanine rings.


    Organizational Affiliation

    Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
PUTATIVE FLUORIDE ION TRANSPORTER CRCBA, B, C, D128Bordetella pertussisMutation(s): 1 
Membrane Entity: Yes 
UniProt
Find proteins for Q7VYU0 (Bordetella pertussis (strain Tohama I / ATCC BAA-589 / NCTC 13251))
Explore Q7VYU0 
Go to UniProtKB:  Q7VYU0
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ7VYU0
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
MONOBODIESE, F, G, H90Homo sapiensMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.60 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.235 
  • R-Value Observed: 0.236 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 146.79α = 90
b = 183.7β = 90
c = 72.88γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
Aimlessdata scaling
SHELXphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-09-02
    Type: Initial release
  • Version 1.1: 2015-09-23
    Changes: Database references
  • Version 1.2: 2015-09-30
    Changes: Database references