1JYS

Crystal Structure of E. coli MTA/AdoHcy Nucleosidase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.217 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of E. coli 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase reveals similarity to the purine nucleoside phosphorylases.

Lee, J.E.Cornell, K.A.Riscoe, M.K.Howell, P.L.

(2001) Structure 9: 941-953

  • DOI: https://doi.org/10.1016/s0969-2126(01)00656-6
  • Primary Citation of Related Structures:  
    1JYS

  • PubMed Abstract: 

    5'-methylthioadenosine/S-adenosyl-homocysteine (MTA/AdoHcy) nucleosidase catalyzes the irreversible cleavage of 5'-methylthioadenosine and S-adenosylhomocysteine to adenine and the corresponding thioribose, 5'-methylthioribose and S-ribosylhomocysteine, respectively. While this enzyme is crucial for the metabolism of AdoHcy and MTA nucleosides in many prokaryotic and lower eukaryotic organisms, it is absent in mammalian cells. This metabolic difference represents an exploitable target for rational drug design. The crystal structure of E. coli MTA/AdoHcy nucleosidase was determined at 1.90 A resolution with the multiwavelength anomalous diffraction (MAD) technique. Each monomer of the MTA/AdoHcy nucleosidase dimer consists of a mixed alpha/beta domain with a nine-stranded mixed beta sheet, flanked by six alpha helices and a small 3(10) helix. Intersubunit contacts between the two monomers present in the asymmetric unit are mediated primarily by helix-helix and helix-loop hydrophobic interactions. The unexpected presence of an adenine molecule in the active site of the enzyme has allowed the identification of both substrate binding and potential catalytic amino acid residues. Although the sequence of E. coli MTA/AdoHcy nucleosidase has almost no identity with any known enzyme, its tertiary structure is similar to both the mammalian (trimeric) and prokaryotic (hexameric) purine nucleoside phosphorylases. The structure provides evidence that this protein is functional as a dimer and that the dual specificity for MTA and AdoHcy results from the truncation of a helix. The structure of MTA/AdoHcy nucleosidase is the first structure of a prokaryotic nucleoside N-ribohydrolase specific for 6-aminopurines.


  • Organizational Affiliation

    Structural Biology and Biochemistry, Research Institute, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
MTA/SAH nucleosidase
A, B
242Escherichia coliMutation(s): 0 
Gene Names: pfs
EC: 3.2.2.9
UniProt
Find proteins for P0AF12 (Escherichia coli (strain K12))
Explore P0AF12 
Go to UniProtKB:  P0AF12
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0AF12
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
ADE PDBBind:  1JYS Ki: 3.00e+5 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.239 
  • R-Value Work: 0.217 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 51.08α = 90
b = 133.03β = 90
c = 70.85γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
CNSrefinement
CNSphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-10-01
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-07
    Changes: Data collection, Database references, Derived calculations