2X9N

High resolution structure of TbPTR1 in complex with cyromazine

• PDB DOI: https://doi.org/10.2210/pdb2X9N/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Trypanosoma brucei brucei
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2010-03-23 Released: 2010-06-30 
• Deposition Author(s): Dawson, A., Tulloch, L.B., Barrack, K.L., Hunter, W.N.

---

Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.15 Å
• R-Value Free: 0.152 
• R-Value Observed: 0.126 

Literature

High-Resolution Structures of Trypanosoma Brucei Pteridine Reductase Ligand Complexes Inform on the Placement of New Molecular Entities in the Active Site of a Potential Drug Target

Dawson, A., Tulloch, L.B., Barrack, K.L., Hunter, W.N.

(2010) Acta Crystallogr D Biol Crystallogr 66: 1334

• PubMed: 21123874 
• DOI: https://doi.org/10.1107/S0907444910040886
• Primary Citation of Related Structures:  
  2X9G, 2X9N, 2X9V, 3MCV


• PubMed Abstract: 
  

  Pteridine reductase (PTR1) is a potential target for drug development against parasitic Trypanosoma and Leishmania species. These protozoa cause serious diseases for which current therapies are inadequate. High-resolution structures have been determined, using data between 1.6 and 1.1 Å resolution, of T. brucei PTR1 in complex with pemetrexed, trimetrexate, cyromazine and a 2,4-diaminopyrimidine derivative. The structures provide insight into the interactions formed by new molecular entities in the enzyme active site with ligands that represent lead compounds for structure-based inhibitor development and to support early-stage drug discovery.

---

Organizational Affiliation: 

Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD15EH, Scotland.

Biological Assembly 1  

Global Symmetry: Dihedral - D2  (Explore in 3D)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 127.03 kDa 
• Atom Count: 9,198 
• Modelled Residue Count: 992 
• Deposited Residue Count: 1,152 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PTERIDINE REDUCTASE	A, B, C, D	288	Trypanosoma brucei brucei	Mutation(s): 0  EC: 1.5.1.33
UniProt
Find proteins for O76290 (Trypanosoma brucei brucei) Explore O76290  Go to UniProtKB:  O76290

Small Molecules

Ligands 6 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
NAP	E [auth A], I [auth B], L [auth C], P [auth D]	NADP NICOTINAMIDE-ADENINE-DINUCLEOTIDE PHOSPHATE C21 H28 N7 O17 P3 XJLXINKUBYWONI-NNYOXOHSSA-N
AX3	F [auth A], J [auth B], M [auth C], Q [auth D]	N~2~-cyclopropyl-1,3,5-triazine-2,4,6-triamine C6 H10 N6 LVQDKIWDGQRHTE-UHFFFAOYSA-N
DTD	G [auth A], N [auth C]	DITHIANE DIOL C4 H8 O2 S2 YPGMOWHXEQDBBV-IMJSIDKUSA-N
D1D	K [auth B], R [auth D]	(4S,5S)-1,2-DITHIANE-4,5-DIOL C4 H8 O2 S2 YPGMOWHXEQDBBV-QWWZWVQMSA-N
ACT	O [auth C]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M
NA	H [auth A], S [auth D]	SODIUM ION Na FKNQFGJONOIPTF-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.15 Å
• R-Value Free: 0.152 
• R-Value Observed: 0.126 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 74.5	α = 90
b = 90	β = 115.5
c = 82.4	γ = 90

Software Package:

Software Name	Purpose
SHELXL-97	refinement
XDS	data reduction
XSCALE	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2010-06-30 
Deposition Author(s): Dawson, A., Tulloch, L.B., Barrack, K.L., Hunter, W.N.

Revision History  

• Version 1.0: 2010-06-30
  Type: Initial release
  
• Version 1.1: 2012-04-11
  Changes: Database references, Refinement description, Version format compliance
• Version 1.2: 2019-05-22
  Changes: Data collection, Other, Refinement description
• Version 1.3: 2024-05-08
  Changes: Data collection, Database references, Derived calculations, Other