One active site, two modes of reduction correlate the mechanism of leishmania pteridine reductase with pterin metabolism and antifolate drug resistance in trpanosomes

Experimental Data Snapshot

  • Resolution: 1.75 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.196 

wwPDB Validation   3D Report Full Report

This is version 1.2 of the entry. See complete history


Pteridine Reductase Mechanism Correlates Pterin Metabolism with Drug Resistance in Trypanosomatid Parasites.

Gourley, D.G.Schuttelkopf, A.Leonard, G.Luba, J.Hardy, L.Beverley, S.Hunter, W.N.

(2001) Nat Struct Biol 8: 521

  • DOI: https://doi.org/10.1038/88584
  • Primary Citation of Related Structures:  
    1E7W, 1E92

  • PubMed Abstract: 

    Pteridine reductase (PTR1) is a short-chain reductase (SDR) responsible for the salvage of pterins in parasitic trypanosomatids. PTR1 catalyzes the NADPH-dependent two-step reduction of oxidized pterins to the active tetrahydro-forms and reduces susceptibility to antifolates by alleviating dihydrofolate reductase (DHFR) inhibition. Crystal structures of PTR1 complexed with cofactor and 7,8-dihydrobiopterin (DHB) or methotrexate (MTX) delineate the enzyme mechanism, broad spectrum of activity and inhibition by substrate or an antifolate. PTR1 applies two distinct reductive mechanisms to substrates bound in one orientation. The first reduction uses the generic SDR mechanism, whereas the second shares similarities with the mechanism proposed for DHFR. Both DHB and MTX form extensive hydrogen bonding networks with NADP(H) but differ in the orientation of the pteridine.

  • Organizational Affiliation

    The Wellcome Trust Biocentre, University of Dundee, Dundee, DD1 5EH, UK.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
A, B
291Leishmania majorMutation(s): 0 
Gene Names: PTR1HMTXRL1063.01LmjF23.0270LmjF_23_0270
EC: (PDB Primary Data), (UniProt)
Find proteins for Q01782 (Leishmania major)
Explore Q01782 
Go to UniProtKB:  Q01782
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ01782
Sequence Annotations
  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
MTX BindingDB:  1E7W Ki: min: 39, max: 180 (nM) from 2 assay(s)
Experimental Data & Validation

Experimental Data

  • Resolution: 1.75 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.196 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 80.312α = 90
b = 80.8β = 90
c = 90.747γ = 90
Software Package:
Software NamePurpose

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2001-09-06
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance