3NMO

Crystal structure of an engineered monomeric CLC-ec1 Cl-/H+ transporter


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.10 Å
  • R-Value Free: 0.303 
  • R-Value Work: 0.263 
  • R-Value Observed: 0.265 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Design, function and structure of a monomeric ClC transporter.

Robertson, J.L.Kolmakova-Partensky, L.Miller, C.

(2010) Nature 468: 844-847

  • DOI: 10.1038/nature09556
  • Primary Citation of Related Structures:  
    3NMO

  • PubMed Abstract: 
  • Channels and transporters of the ClC family cause the transmembrane movement of inorganic anions in service of a variety of biological tasks, from the unusual-the generation of the kilowatt pulses with which electric fish stun their prey-to the quotidian-the acidification of endosomes, vacuoles and lysosomes ...

    Channels and transporters of the ClC family cause the transmembrane movement of inorganic anions in service of a variety of biological tasks, from the unusual-the generation of the kilowatt pulses with which electric fish stun their prey-to the quotidian-the acidification of endosomes, vacuoles and lysosomes. The homodimeric architecture of ClC proteins, initially inferred from single-molecule studies of an elasmobranch Cl(-) channel and later confirmed by crystal structures of bacterial Cl(-)/H(+) antiporters, is apparently universal. Moreover, the basic machinery that enables ion movement through these proteins-the aqueous pores for anion diffusion in the channels and the ion-coupling chambers that coordinate Cl(-) and H(+) antiport in the transporters-are contained wholly within each subunit of the homodimer. The near-normal function of a bacterial ClC transporter straitjacketed by covalent crosslinks across the dimer interface and the behaviour of a concatemeric human homologue argue that the transport cycle resides within each subunit and does not require rigid-body rearrangements between subunits. However, this evidence is only inferential, and because examples are known in which quaternary rearrangements of extramembrane ClC domains that contribute to dimerization modulate transport activity, we cannot declare as definitive a 'parallel-pathways' picture in which the homodimer consists of two single-subunit transporters operating independently. A strong prediction of such a view is that it should in principle be possible to obtain a monomeric ClC. Here we exploit the known structure of a ClC Cl(-)/H(+) exchanger, ClC-ec1 from Escherichia coli, to design mutants that destabilize the dimer interface while preserving both the structure and the transport function of individual subunits. The results demonstrate that the ClC subunit alone is the basic functional unit for transport and that cross-subunit interaction is not required for Cl(-)/H(+) exchange in ClC transporters.


    Organizational Affiliation

    Department of Biochemistry, Howard Hughes Medical Institute, Brandeis University, Waltham, Massachusetts 02454, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
H(+)/Cl(-) exchange transporter clcAA465Escherichia coli 042Mutation(s): 2 
Gene Names: clcA
Membrane Entity: Yes 
UniProt
Find proteins for P37019 (Escherichia coli (strain K12))
Explore P37019 
Go to UniProtKB:  P37019
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download Ideal Coordinates CCD File 
B [auth A]CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.10 Å
  • R-Value Free: 0.303 
  • R-Value Work: 0.263 
  • R-Value Observed: 0.265 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 200.745α = 90
b = 60.332β = 94.27
c = 70.025γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
PHASERphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2010-07-21
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance