4I0U

Improved structure of Thermotoga maritima CorA at 2.7 A resolution


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.228 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Exploring the structure and function of Thermotoga maritima CorA reveals the mechanism of gating and ion selectivity in Co2+/Mg2+ transport.

Nordin, N.Guskov, A.Phua, T.Sahaf, N.Xia, Y.Lu, S.Y.Eshaghi, H.Eshaghi, S.

(2013) Biochem.J. 451: 365-374

  • DOI: 10.1042/BJ20121745

  • PubMed Abstract: 
  • The CorA family of divalent cation transporters utilizes Mg2+ and Co2+ as primary substrates. The molecular mechanism of its function, including ion selectivity and gating, has not been fully characterized. Recently we reported a new structure of a C ...

    The CorA family of divalent cation transporters utilizes Mg2+ and Co2+ as primary substrates. The molecular mechanism of its function, including ion selectivity and gating, has not been fully characterized. Recently we reported a new structure of a CorA homologue from Methanocaldococcus jannaschii, which provided novel structural details that offered the conception of a unique gating mechanism involving conversion of an open hydrophilic gate into a closed hydrophobic one. In the present study we report functional evidence for this novel gating mechanism in the Thermotoga maritima CorA together with an improved crystal structure of this CorA to 2.7 Å (1 Å=0.1 nm) resolution. The latter reveals the organization of the selectivity filter to be similar to that of M. jannaschii CorA and also the previously unknown organization of the second signature motif of the CorA family. The proposed gating is achieved by a helical rotation upon the binding of a metal ion substrate to the regulatory binding sites. Additionally, our data suggest that the preference of this CorA for Co2+ over Mg2+ is controlled by the presence of threonine side chains in the channel. Finally, the roles of the intracellular metal-binding sites have been assigned to increased thermostability and regulation of the gating. These mechanisms most likely apply to the entire CorA family as they are regulated by the highly conserved amino acids.


    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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Magnesium transport protein CorA
A, B, C, D, E, F, G, H, I, J
351Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)Gene Names: corA
Find proteins for Q9WZ31 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099))
Go to UniProtKB:  Q9WZ31
Small Molecules
Ligands 5 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H, J
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, I, J
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
PG0
Query on PG0

Download SDF File 
Download CCD File 
E
2-(2-METHOXYETHOXY)ETHANOL
PEG 6000
C5 H12 O3
SBASXUCJHJRPEV-UHFFFAOYSA-N
 Ligand Interaction
LMT
Query on LMT

Download SDF File 
Download CCD File 
A, B
DODECYL-BETA-D-MALTOSIDE
C24 H46 O11
NLEBIOOXCVAHBD-QKMCSOCLSA-N
 Ligand Interaction
PEG
Query on PEG

Download SDF File 
Download CCD File 
B, C, D, E, F, G, H, I, J
DI(HYDROXYETHYL)ETHER
C4 H10 O3
MTHSVFCYNBDYFN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.7 Å
  • R-Value Free: 0.289 
  • R-Value Work: 0.228 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 116.250α = 90.00
b = 151.500β = 98.88
c = 143.360γ = 90.00
Software Package:
Software NamePurpose
XSCALEdata scaling
XDSdata reduction
HKL-2000data collection
PHASERphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-03-06
    Type: Initial release
  • Version 1.1: 2014-09-10
    Type: Database references