3GN2

Structure of Pteridine Reductase 1 (PTR1) from TRYPANOSOMA BRUCEI in ternary complex with cofactor (NADP+) and inhibitor (DDD00066730)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.146 
  • R-Value Observed: 0.148 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.3 of the entry. See complete history


Literature

One scaffold, three binding modes: novel and selective pteridine reductase 1 inhibitors derived from fragment hits discovered by virtual screening.

Mpamhanga, C.P.Spinks, D.Tulloch, L.B.Shanks, E.J.Robinson, D.A.Collie, I.T.Fairlamb, A.H.Wyatt, P.G.Frearson, J.A.Hunter, W.N.Gilbert, I.H.Brenk, R.

(2009) J Med Chem 52: 4454-4465

  • DOI: https://doi.org/10.1021/jm900414x
  • Primary Citation of Related Structures:  
    2WD7, 2WD8, 3GN1, 3GN2

  • PubMed Abstract: 

    The enzyme pteridine reductase 1 (PTR1) is a potential target for new compounds to treat human African trypanosomiasis. A virtual screening campaign for fragments inhibiting PTR1 was carried out. Two novel chemical series were identified containing aminobenzothiazole and aminobenzimidazole scaffolds, respectively. One of the hits (2-amino-6-chloro-benzimidazole) was subjected to crystal structure analysis and a high resolution crystal structure in complex with PTR1 was obtained, confirming the predicted binding mode. However, the crystal structures of two analogues (2-amino-benzimidazole and 1-(3,4-dichloro-benzyl)-2-amino-benzimidazole) in complex with PTR1 revealed two alternative binding modes. In these complexes, previously unobserved protein movements and water-mediated protein-ligand contacts occurred, which prohibited a correct prediction of the binding modes. On the basis of the alternative binding mode of 1-(3,4-dichloro-benzyl)-2-amino-benzimidazole, derivatives were designed and selective PTR1 inhibitors with low nanomolar potency and favorable physicochemical properties were obtained.


  • Organizational Affiliation

    Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Pteridine reductase
A, B, C, D
288Trypanosoma brucei bruceiMutation(s): 0 
Gene Names: PTR1
UniProt
Find proteins for O76290 (Trypanosoma brucei brucei)
Explore O76290 
Go to UniProtKB:  O76290
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO76290
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
NAP
Query on NAP

Download Ideal Coordinates CCD File 
E [auth A],
H [auth B],
J [auth C],
L [auth D]
NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE
C21 H28 N7 O17 P3
XJLXINKUBYWONI-NNYOXOHSSA-N
AX8
Query on AX8

Download Ideal Coordinates CCD File 
F [auth A],
I [auth B],
K [auth C],
M [auth D],
N [auth D]
1-(3,4-dichlorobenzyl)-1H-benzimidazol-2-amine
C14 H11 Cl2 N3
JBNABAJVIVYIDA-UHFFFAOYSA-N
ACT
Query on ACT

Download Ideal Coordinates CCD File 
G [auth A]ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
Binding Affinity Annotations 
IDSourceBinding Affinity
AX8 BindingDB:  3GN2 Ki: 400 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.60 Å
  • R-Value Free: 0.178 
  • R-Value Work: 0.146 
  • R-Value Observed: 0.148 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 74.895α = 90
b = 90.778β = 115.85
c = 82.861γ = 90
Software Package:
Software NamePurpose
MOLREPphasing
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2009-12-29
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Advisory, Refinement description, Version format compliance
  • Version 1.2: 2011-09-07
    Changes: Atomic model, Database references
  • Version 1.3: 2024-02-21
    Changes: Data collection, Database references, Derived calculations