5A67

Crystal structure of AtTTM3 in complex with tripolyphosphate and manganese ion (form B)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.3 Å
  • R-Value Free: 0.175 
  • R-Value Work: 0.140 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structural Determinants for Substrate Binding and Catalysis in Triphosphate Tunnel Metalloenzymes.

Martinez, J.Truffault, V.Hothorn, M.

(2015) J.Biol.Chem. 290: 23348

  • DOI: 10.1074/jbc.M115.674473
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Triphosphate tunnel metalloenzymes (TTMs) are present in all kingdoms of life and catalyze diverse enzymatic reactions such as mRNA capping, the cyclization of adenosine triphosphate, the hydrolysis of thiamine triphosphate, and the synthesis and bre ...

    Triphosphate tunnel metalloenzymes (TTMs) are present in all kingdoms of life and catalyze diverse enzymatic reactions such as mRNA capping, the cyclization of adenosine triphosphate, the hydrolysis of thiamine triphosphate, and the synthesis and breakdown of inorganic polyphosphates. TTMs have an unusual tunnel domain fold that harbors substrate- and metal co-factor binding sites. It is presently poorly understood how TTMs specifically sense different triphosphate-containing substrates and how catalysis occurs in the tunnel center. Here we describe substrate-bound structures of inorganic polyphosphatases from Arabidopsis and Escherichia coli, which reveal an unorthodox yet conserved mode of triphosphate and metal co-factor binding. We identify two metal binding sites in these enzymes, with one co-factor involved in substrate coordination and the other in catalysis. Structural comparisons with a substrate- and product-bound mammalian thiamine triphosphatase and with previously reported structures of mRNA capping enzymes, adenylate cyclases, and polyphosphate polymerases suggest that directionality of substrate binding defines TTM catalytic activity. Our work provides insight into the evolution and functional diversification of an ancient enzyme family.


    Organizational Affiliation

    From the Structural Plant Biology Laboratory, Department of Botany and Plant Biology, University of Geneva, 1211 Geneva, Switzerland and.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TRIPHOSPHATE TUNEL METALLOENZYME 3
A
212Arabidopsis thalianaMutation(s): 0 
Gene Names: TTM3
Find proteins for Q9SIY3 (Arabidopsis thaliana)
Go to UniProtKB:  Q9SIY3
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MN
Query on MN

Download SDF File 
Download CCD File 
A
MANGANESE (II) ION
Mn
WAEMQWOKJMHJLA-UHFFFAOYSA-N
 Ligand Interaction
3PO
Query on 3PO

Download SDF File 
Download CCD File 
A
TRIPHOSPHATE
H5 O10 P3
UNXRWKVEANCORM-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.3 Å
  • R-Value Free: 0.175 
  • R-Value Work: 0.140 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 44.375α = 90.00
b = 33.868β = 94.97
c = 72.216γ = 90.00
Software Package:
Software NamePurpose
XDSdata reduction
XDSdata scaling
PHASERphasing
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-08-05
    Type: Initial release
  • Version 1.1: 2015-08-12
    Type: Database references
  • Version 1.2: 2015-10-07
    Type: Database references
  • Version 1.3: 2017-08-23
    Type: Data collection