4A01

Crystal Structure of the H-Translocating Pyrophosphatase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.203 
  • R-Value Work: 0.168 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Crystal Structure of a Membrane Embedded H1-Translocating Pyrophosphatase

Lin, S.-M.Tsai, J.-Y.Hsiao, C.-D.Chiu, C.-L.Pan, R.-L.Sun, Y.-J.

(2012) Nature 484: 399

  • DOI: 10.1038/nature10963

  • PubMed Abstract: 
  • H(+)-translocating pyrophosphatases (H(+)-PPases) are active proton transporters that establish a proton gradient across the endomembrane by means of pyrophosphate (PP(i)) hydrolysis. H(+)-PPases are found primarily as homodimers in the vacuolar memb ...

    H(+)-translocating pyrophosphatases (H(+)-PPases) are active proton transporters that establish a proton gradient across the endomembrane by means of pyrophosphate (PP(i)) hydrolysis. H(+)-PPases are found primarily as homodimers in the vacuolar membrane of plants and the plasma membrane of several protozoa and prokaryotes. The three-dimensional structure and detailed mechanisms underlying the enzymatic and proton translocation reactions of H(+)-PPases are unclear. Here we report the crystal structure of a Vigna radiata H(+)-PPase (VrH(+)-PPase) in complex with a non-hydrolysable substrate analogue, imidodiphosphate (IDP), at 2.35 Å resolution. Each VrH(+)-PPase subunit consists of an integral membrane domain formed by 16 transmembrane helices. IDP is bound in the cytosolic region of each subunit and trapped by numerous charged residues and five Mg(2+) ions. A previously undescribed proton translocation pathway is formed by six core transmembrane helices. Proton pumping can be initialized by PP(i) hydrolysis, and H(+) is then transported into the vacuolar lumen through a pathway consisting of Arg 242, Asp 294, Lys 742 and Glu 301. We propose a working model of the mechanism for the coupling between proton pumping and PP(i) hydrolysis by H(+)-PPases.


    Organizational Affiliation

    Department of Life Science and Institute of Bioinformatics and Structural Biology, College of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PROTON PYROPHOSPHATASE
A, B
766Vigna radiata var. radiataEC: 3.6.1.1
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Membrane-Integral Pyrophosphatases (M-PPases)
Protein: 
H+-translocating M-PPase
Find proteins for P21616 (Vigna radiata var. radiata)
Go to UniProtKB:  P21616
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
K
Query on K

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Download CCD File 
A, B
POTASSIUM ION
K
NPYPAHLBTDXSSS-UHFFFAOYSA-N
 Ligand Interaction
DMU
Query on DMU

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Download CCD File 
A, B
DECYL-BETA-D-MALTOPYRANOSIDE
DECYLMALTOSIDE
C22 H42 O11
WOQQAWHSKSSAGF-WXFJLFHKSA-N
 Ligand Interaction
MG
Query on MG

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Download CCD File 
A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
2PN
Query on 2PN

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Download CCD File 
A, B
IMIDODIPHOSPHORIC ACID
H5 N O6 P2
GNGSOPFGGKKDQP-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.35 Å
  • R-Value Free: 0.203 
  • R-Value Work: 0.168 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 218.619α = 90.00
b = 88.241β = 125.53
c = 159.105γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data reduction
PHENIXphasing
REFMACrefinement
SCALEPACKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-03-28
    Type: Initial release
  • Version 1.1: 2012-04-25
    Type: Other