3JCH

Cryo-EM structure of the magnesium channel CorA in the magnesium-free, asymmetric open state II


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 7.06 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Cryo-EM Structures of the Magnesium Channel CorA Reveal Symmetry Break upon Gating.

Matthies, D.Dalmas, O.Borgnia, M.J.Dominik, P.K.Merk, A.Rao, P.Reddy, B.G.Islam, S.Bartesaghi, A.Perozo, E.Subramaniam, S.

(2016) Cell 164: 747-756

  • DOI: 10.1016/j.cell.2015.12.055
  • Primary Citation of Related Structures:  
    3JCF, 3JCG, 3JCH

  • PubMed Abstract: 
  • CorA, the major Mg(2+) uptake system in prokaryotes, is gated by intracellular Mg(2+) (KD ∼ 1-2 mM). X-ray crystallographic studies of CorA show similar conformations under Mg(2+)-bound and Mg(2+)-free conditions, but EPR spectroscopic studies reveal large Mg(2+)-driven quaternary conformational changes ...

    CorA, the major Mg(2+) uptake system in prokaryotes, is gated by intracellular Mg(2+) (KD ∼ 1-2 mM). X-ray crystallographic studies of CorA show similar conformations under Mg(2+)-bound and Mg(2+)-free conditions, but EPR spectroscopic studies reveal large Mg(2+)-driven quaternary conformational changes. Here, we determined cryo-EM structures of CorA in the Mg(2+)-bound closed conformation and in two open Mg(2+)-free states at resolutions of 3.8, 7.1, and 7.1 Å, respectively. In the absence of bound Mg(2+), four of the five subunits are displaced to variable extents (∼ 10-25 Å) by hinge-like motions as large as ∼ 35° at the stalk helix. The transition between a single 5-fold symmetric closed state and an ensemble of low Mg(2+), open, asymmetric conformational states is, thus, the key structural signature of CorA gating. This mechanism is likely to apply to other structurally similar divalent ion channels.


    Organizational Affiliation

    Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD 20892, USA. Electronic address: ss1@nih.gov.



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Magnesium transport protein CorA ABCDE351Thermotoga maritimaMutation(s): 0 
Gene Names: corATM_0561
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
CorA Superfamily Ion Transporters
Protein: 
CorA Mg2+ Transporter, cryo-EM structure, closed state
Find proteins for Q9WZ31 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099))
Explore Q9WZ31 
Go to UniProtKB:  Q9WZ31
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 7.06 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2016-02-17
    Type: Initial release
  • Version 1.1: 2016-03-02
    Changes: Database references
  • Version 1.2: 2018-07-18
    Changes: Data collection
  • Version 1.3: 2019-12-18
    Changes: Other