6D0J

Crystal structure of a CLC-type fluoride/proton antiporter

Summary for 6D0J

• Entry DOI: 10.2210/pdb6d0j/pdb
• Descriptor: CLC-type fluoride/proton antiporter, Monobody, DECYL-BETA-D-MALTOPYRANOSIDE, ... (6 entities in total)
• Functional Keywords: fluoride/proton antiporter clc membrane protein, transport protein
• Biological source: Enterococcus casseliflavus (strain EC10); More
• Total number of polymer chains: 4
• Total formula weight: 114224.64

Authors

Last, N.B.,Stockbridge, R.B.,Wilson, A.E.,Shane, T.,Kolmakova-Partensky, L.,Koide, A.,Koide, S.,Miller, C. (deposition date: 2018-04-10, release date: 2018-07-04, Last modification date: 2023-10-04)

Primary citation

Last, N.B.,Stockbridge, R.B.,Wilson, A.E.,Shane, T.,Kolmakova-Partensky, L.,Koide, A.,Koide, S.,Miller, C.
A CLC-type F-/H+antiporter in ion-swapped conformations.
Nat. Struct. Mol. Biol., 25:601-606, 2018

PubMed Abstract: Fluoride/proton antiporters of the CLC family combat F toxicity in bacteria by exporting this halide from the cytoplasm. These transporters belong to the widespread CLC superfamily but display transport properties different from those of the well-studied Cl/H antiporters. Here, we report a structural and functional investigation of these F-transport proteins. Crystal structures of a CLC homolog from Enterococcus casseliflavus are captured in two conformations with simultaneous accessibility of F and H ions via separate pathways on opposite sides of the membrane. Manipulation of a key glutamate residue critical for H and F transport reverses the anion selectivity of transport; replacement of the glutamate with glutamine or alanine completely inhibits F and H transport while allowing for rapid uncoupled flux of Cl. The structural and functional results lead to a 'windmill' model of CLC antiport wherein F and H simultaneously move through separate ion-specific pathways that switch sidedness during the transport cycle.

PubMed: 29941917
DOI: 10.1038/s41594-018-0082-0

Experimental method

X-RAY DIFFRACTION (3 Å)