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 (Depositor), 0.180 (DCC) 
  • R-Value Work: 
    0.146 (Depositor), 0.150 (DCC) 
  • R-Value Observed: 
    0.148 (Depositor) 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 

Created with Raphaël 2.3.0Worse 01 BetterLigand structure goodness of fit to experimental dataBest fitted NAPClick on this verticalbar to view detailsBest fitted AX8Click on this verticalbar to view details

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 (Depositor), 0.180 (DCC) 
  • R-Value Work:  0.146 (Depositor), 0.150 (DCC) 
  • R-Value Observed: 0.148 (Depositor) 
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 

Created with Raphaël 2.3.0Worse 01 BetterLigand structure goodness of fit to experimental dataBest fitted NAPClick on this verticalbar to view detailsBest fitted AX8Click on this verticalbar to view details

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