4FG6

Structure of EcCLC E148A mutant in Glutamate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.019 Å
  • R-Value Free: 0.274 
  • R-Value Work: 0.237 

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

Molecular mechanism of proton transport in CLC Cl-/H+ exchange transporters.

Feng, L.Campbell, E.B.MacKinnon, R.

(2012) Proc.Natl.Acad.Sci.USA 109: 11699-11704

  • DOI: 10.1073/pnas.1205764109

  • PubMed Abstract: 
  • CLC proteins underlie muscle, kidney, bone, and other organ system function by catalyzing the transport of Cl(-) ions across cell and organellar membranes. Some CLC proteins are ion channels while others are pumps that exchange Cl(-) for H(+). The pa ...

    CLC proteins underlie muscle, kidney, bone, and other organ system function by catalyzing the transport of Cl(-) ions across cell and organellar membranes. Some CLC proteins are ion channels while others are pumps that exchange Cl(-) for H(+). The pathway through which Cl(-) ions cross the membrane has been characterized, but the transport of H(+) and the principle by which their movement is coupled to Cl(-) movement is not well understood. Here we show that H(+) transport depends not only on the presence of a specific glutamate residue but also the presence of Cl(-) ions. H(+) transport, however, can be isolated and analyzed in the absence of Cl(-) by mutating the glutamate to alanine and adding carboxylate-containing molecules to solution, consistent with the notion that H(+) transfer is mediated through the entry of a carboxylate group into the anion pathway. Cl(-) ions and carboxylate interact with each other strongly. These data support a mechanism in which the glutamate carboxylate functions as a surrogate Cl(-) ion, but it can accept a H(+) and transfer it between the external solution and the central Cl(-) binding site, coupled to the movement of 2 Cl(-) ions.


    Organizational Affiliation

    Laboratory of Molecular Neurobiology and Biophysics, Rockefeller University, Howard Hughes Medical Institute, 1230 York Avenue, New York, NY 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
H(+)/Cl(-) exchange transporter ClcA
A, B
465Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: clcA (eriC, yadQ)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
H+/Cl- or F- Exchange Transporters
Protein: 
H+/Cl- Exchange Transporter
Find proteins for P37019 (Escherichia coli (strain K12))
Go to UniProtKB:  P37019
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Fab fragment (Heavy chain)
C, E
222N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Fab fragment (Light chain)
D, F
211N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.019 Å
  • R-Value Free: 0.274 
  • R-Value Work: 0.237 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 221.455α = 90.00
b = 121.284β = 128.08
c = 151.698γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
PHENIXrefinement
DENZOdata reduction
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-07-04
    Type: Initial release
  • Version 1.1: 2012-07-25
    Type: Database references
  • Version 1.2: 2013-01-02
    Type: Database references
  • Version 1.3: 2016-11-09
    Type: Structure summary
  • Version 1.4: 2017-11-08
    Type: Refinement description, Source and taxonomy