1E9G

STRUCTURE OF INORGANIC PYROPHOSPHATASE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.15 Å

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history


Literature

Toward a Quantum-Mechanical Description of Metal-Assisted Phosphoryl Transfer in Pyrophosphatase

Heikinheimo, P.Tuominen, V.Ahonen, A.-K.Teplyakov, A.Cooperman, B.S.Baykov, A.A.Lahti, R.Goldman, A.

(2001) Proc Natl Acad Sci U S A 98: 3121

  • DOI: 10.1073/pnas.061612498
  • Primary Citation of Related Structures:  
    1E6A, 1E9G

  • PubMed Abstract: 
  • The wealth of kinetic and structural information makes inorganic pyrophosphatases (PPases) a good model system to study the details of enzymatic phosphoryl transfer. The enzyme accelerates metal-complexed phosphoryl transfer 10(10)-fold: but how? Our ...

    The wealth of kinetic and structural information makes inorganic pyrophosphatases (PPases) a good model system to study the details of enzymatic phosphoryl transfer. The enzyme accelerates metal-complexed phosphoryl transfer 10(10)-fold: but how? Our structures of the yeast PPase product complex at 1.15 A and fluoride-inhibited complex at 1.9 A visualize the active site in three different states: substrate-bound, immediate product bound, and relaxed product bound. These span the steps around chemical catalysis and provide strong evidence that a water molecule (O(nu)) directly attacks PPi with a pK(a) vastly lowered by coordination to two metal ions and D117. They also suggest that a low-barrier hydrogen bond (LBHB) forms between D117 and O(nu), in part because of steric crowding by W100 and N116. Direct visualization of the double bonds on the phosphates appears possible. The flexible side chains at the top of the active site absorb the motion involved in the reaction, which may help accelerate catalysis. Relaxation of the product allows a new nucleophile to be generated and creates symmetry in the elementary catalytic steps on the enzyme. We are thus moving closer to understanding phosphoryl transfer in PPases at the quantum mechanical level. Ultra-high resolution structures can thus tease out overlapping complexes and so are as relevant to discussion of enzyme mechanism as structures produced by time-resolved crystallography.


    Organizational Affiliation

    Center for Biotechnology, PL 123, FIN-20521 Turku, Finland.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
INORGANIC PYROPHOSPHATASEAB286Saccharomyces cerevisiaeMutation(s): 0 
Gene Names: PPA1
EC: 3.6.1.1
Find proteins for P00817 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P00817 
Go to UniProtKB:  P00817
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download CCD File 
A, B
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
MN
Query on MN

Download CCD File 
A, B
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.15 Å
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 58.318α = 90
b = 103.087β = 90
c = 116.518γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing
SHELXLphasing
SHELXL-97refinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-03-19
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2019-05-22
    Changes: Data collection, Other, Refinement description
  • Version 1.4: 2019-07-24
    Changes: Data collection