3AOU

Structure of the Na+ unbound rotor ring modified with N,N f-Dicyclohexylcarbodiimide of the Na+-transporting V-ATPase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.14 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.211 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of the rotor ring modified with N,N'-dicyclohexylcarbodiimide of the Na+-transporting vacuolar ATPase.

Mizutani, K.Yamamoto, M.Suzuki, K.Yamato, I.Kakinuma, Y.Shirouzu, M.Walker, J.E.Yokoyama, S.Iwata, S.Murata, T.

(2011) Proc Natl Acad Sci U S A 108: 13474-13479

  • DOI: 10.1073/pnas.1103287108
  • Primary Citation of Related Structures:  
    3AOU, 2DB4

  • PubMed Abstract: 
  • The prokaryotic V-ATPase of Enterococcus hirae, closely related to the eukaryotic enzymes, provides a unique opportunity to study the ion-translocation mechanism because it transports Na(+), which can be detected by radioisotope (22Na(+)) experiments ...

    The prokaryotic V-ATPase of Enterococcus hirae, closely related to the eukaryotic enzymes, provides a unique opportunity to study the ion-translocation mechanism because it transports Na(+), which can be detected by radioisotope (22Na(+)) experiments and X-ray crystallography. In this study, we demonstrated that the binding affinity of the rotor ring (K ring) for 22Na(+) decreased approximately 30-fold by reaction with N,N(')-dicyclohexylcarbodiimide (DCCD), and determined the crystal structures of Na(+)-bound and Na(+)-unbound K rings modified with DCCD at 2.4- and 3.1-Å resolutions, respectively. Overall these structures were similar, indicating that there is no global conformational change associated with release of Na(+) from the DCCD-K ring. A conserved glutamate residue (E139) within all 10 ion-binding pockets of the K ring was neutralized by modification with DCCD, and formed an "open" conformation by losing hydrogen bonds with the Y68 and T64 side chains, resulting in low affinity for Na(+). This open conformation is likely to be comparable to that of neutralized E139 forming a salt bridge with the conserved arginine of the stator during the ion-translocation process. Based on these findings, we proposed the ion-translocation model that the binding affinity for Na(+) decreases due to the neutralization of E139, thus releasing bound Na(+), and that the structures of Na(+)-bound and Na(+)-unbound DCCD-K rings are corresponding to intermediate states before and after release of Na(+) during rotational catalysis of V-ATPase, respectively.


    Organizational Affiliation

    Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
V-type sodium ATPase subunit KABCDEFGHIJ156Enterococcus hiraeMutation(s): 0 
Gene Names: ntpKntpN
Find proteins for P43457 (Enterococcus hirae (strain ATCC 9790 / DSM 20160 / JCM 8729 / LMG 6399 / NBRC 3181 / NCIMB 6459 / NCDO 1258))
Explore P43457 
Go to UniProtKB:  P43457
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.14 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.209 
  • R-Value Observed: 0.211 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 120.41α = 90
b = 124.937β = 90
c = 208.221γ = 90
Software Package:
Software NamePurpose
BSSdata collection
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2011-08-17
    Type: Initial release
  • Version 1.1: 2012-05-23
    Changes: Non-polymer description
  • Version 1.2: 2013-08-07
    Changes: Database references
  • Version 1.3: 2017-10-11
    Changes: Refinement description