5KOM

The crystal structure of fluoride channel Fluc Ec2 F83I Mutant

Summary for 5KOM

• Entry DOI: 10.2210/pdb5kom/pdb
• Descriptor: Putative fluoride ion transporter CrcB, monobody, SODIUM ION, ... (6 entities in total)
• Functional Keywords: alpha helix, ion channel, membrane protein, transport protein
• Biological source: Escherichia coli; More
• Total number of polymer chains: 4
• Total formula weight: 53877.27

Authors

Last, N.B.,Kolmakova-Partensky, L.,Shane, T.,Miller, C. (deposition date: 2016-06-30, release date: 2016-08-03, Last modification date: 2023-10-04)

Primary citation

Last, N.B.,Kolmakova-Partensky, L.,Shane, T.,Miller, C.
Mechanistic signs of double-barreled structure in a fluoride ion channel.
Elife, 5:-, 2016

PubMed Abstract: The Fluc family of F(-) ion channels protects prokaryotes and lower eukaryotes from the toxicity of environmental F(-). In bacteria, these channels are built as dual-topology dimers whereby the two subunits assemble in antiparallel transmembrane orientation. Recent crystal structures suggested that Fluc channels contain two separate ion-conduction pathways, each with two F(-) binding sites, but no functional correlates of this unusual architecture have been reported. Experiments here fill this gap by examining the consequences of mutating two conserved F(-)-coordinating phenylalanine residues. Substitution of each phenylalanine specifically extinguishes its associated F(-) binding site in crystal structures and concomitantly inhibits F(-) permeation. Functional analysis of concatemeric channels, which permit mutagenic manipulation of individual pores, show that each pore can be separately inactivated without blocking F(-) conduction through its symmetry-related twin. The results strongly support dual-pathway architecture of Fluc channels.

PubMed: 27449280
DOI: 10.7554/eLife.18767

Experimental method

X-RAY DIFFRACTION (2.69 Å)