4EV6

The complete structure of CorA magnesium transporter from Methanocaldococcus jannaschii


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.20 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.205 
  • R-Value Observed: 0.209 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Structural insights into the mechanisms of Mg2+ uptake, transport, and gating by CorA

Guskov, A.Nordin, N.Reynaud, A.Engman, H.Lundback, A.K.Jong, A.J.Cornvik, T.Phua, T.Eshaghi, S.

(2012) Proc Natl Acad Sci U S A 109: 18459-18464

  • DOI: 10.1073/pnas.1210076109
  • Primary Citation of Related Structures:  
    4EGW, 4EV6

  • PubMed Abstract: 
  • Despite the importance of Mg(2+) for numerous cellular activities, the mechanisms underlying its import and homeostasis are poorly understood. The CorA family is ubiquitous and is primarily responsible for Mg(2+) transport. However, the key questions ...

    Despite the importance of Mg(2+) for numerous cellular activities, the mechanisms underlying its import and homeostasis are poorly understood. The CorA family is ubiquitous and is primarily responsible for Mg(2+) transport. However, the key questions-such as, the ion selectivity, the transport pathway, and the gating mechanism-have remained unanswered for this protein family. We present a 3.2 Å resolution structure of the archaeal CorA from Methanocaldococcus jannaschii, which is a unique complete structure of a CorA protein and reveals the organization of the selectivity filter, which is composed of the signature motif of this family. The structure reveals that polar residues facing the channel coordinate a partially hydrated Mg(2+) during the transport. Based on these findings, we propose a unique gating mechanism involving a helical turn upon the binding of Mg(2+) to the regulatory intracellular binding sites, and thus converting a polar ion passage into a narrow hydrophobic pore. Because the amino acids involved in the uptake, transport, and gating are all conserved within the entire CorA family, we believe this mechanism is general for the whole family including the eukaryotic homologs.


    Organizational Affiliation

    Division of Structural Biology and Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore 637551, Republic of Singapore.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Magnesium transport protein CorAABCDE339Methanocaldococcus jannaschii DSM 2661Mutation(s): 0 
Gene Names: corAMJ1033
Find proteins for Q58439 (Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440))
Explore Q58439 
Go to UniProtKB:  Q58439
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
UMQ
Query on UMQ

Download CCD File 
A, B, C, D, E
UNDECYL-MALTOSIDE
C23 H44 O11
UYEMNFYVTFDKRG-ZNGNCRBCSA-N
 Ligand Interaction
MG
Query on MG

Download CCD File 
A, B, C, D, E
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.20 Å
  • R-Value Free: 0.282 
  • R-Value Work: 0.205 
  • R-Value Observed: 0.209 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 103.11α = 90
b = 124.83β = 90.76
c = 111.88γ = 90
Software Package:
Software NamePurpose
ADSCdata collection
PHASERphasing
PHENIXrefinement
XDSdata reduction
XDSdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-10-31
    Type: Initial release
  • Version 1.1: 2013-07-24
    Changes: Database references