Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 54.59 kDa 
• Atom Count: 4860 
• Modelled Residue Count: 466 
• Deposited Residue Count: 466 
• Unique protein chains: 1

1FSG

TOXOPLASMA GONDII HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE COMPLEXED WITH 9-DEAZAGUANINE, ALPHA-D-5-PHOSPHORIBOSYL-1-PYROPHOSPHATE (PRPP) AND TWO MG2+ IONS

• DOI: 10.2210/pdb1FSG/pdb

• Classification: TRANSFERASE
• Organism(s): Toxoplasma gondii RH
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2000-09-08 Released: 2000-12-06 
• Deposition Author(s): Heroux, A., White, E.L., Ross, L.J., Kuzin, A.P., Borhani, D.W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.05 Å
• R-Value Free: 0.154 
• R-Value Work: 0.122 

Literature

Substrate deformation in a hypoxanthine-guanine phosphoribosyltransferase ternary complex: the structural basis for catalysis.

Heroux, A., White, E.L., Ross, L.J., Kuzin, A.P., Borhani, D.W.

(2000) Structure 8: 1309-1318

• PubMed: 11188695 
• DOI: 10.1016/s0969-2126(00)00546-3
• Primary Citation of Related Structures:  
  1FSG


• PubMed Abstract: 
  

Hypoxanthine-guanine phosphoribosyltransferases (HGPRTs) are well-recognized antiparasitic drug targets. HGPRT is also a paradigmatic representative of the phosphoribosyltransferase family of enzymes, which includes other important biosynthetic and salvage enzymes and drug targets. To better understand the reaction mechanism of this enzyme, we have crystallized HGPRT from the apicomplexan protozoan Toxoplasma gondii as a ternary complex with a substrate and a substrate analog.

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Related Citations: 

• Crystal Structures of the Toxoplasma Gondii Hypoxanthine-Guanine Phosphoribosyltransferase-GMP and -IMP Complexes:Comparison of purine binding Interactions with the XMP Complex
  Heroux, A., White, E.L., Ross, L.J., Davis, R.L., Borhani, D.W.
  (1999) Biochemistry 38: 14485

• Crystal Structure of Toxoplasma Gondii Hypoxanthine-Guanine Phosphoribosyltransferase with XMP, Pyrophosphate, and Two Mg(2+) Ions Bound:Insights into the Catalytic Mechanism
  Heroux, A., White, E.L., Ross, L.J., Borhani, D.W.
  (1999) Biochemistry 38: 14495

• Isolation and Sequencing of a Cdna Encoding the Hypoxanthine-Guanine Phosphoribosyltransferase from Toxoplasma Gondii
  Vasanthakumar, G., van Ginkel, S., Parish, G.
  (1994) Gene 147: 153

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Organizational Affiliation: 

Drug Discovery Division, Southern Research Institute, Birmingham, Alabama 35205, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
HYPOXANTHINE-GUANINE PHOSPHORIBOSYLTRANSFERASE	A, B [auth C]	233	Toxoplasma gondii RH	Mutation(s): 0  EC: 2.4.2.8 (PDB Primary Data), 2.4.2.22 (UniProt)
Find proteins for Q26997 (Toxoplasma gondii) Explore Q26997  Go to UniProtKB:  Q26997

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PRP	E [auth A], I [auth C]	1-O-pyrophosphono-5-O-phosphono-alpha-D-ribofuranose C5 H13 O14 P3 PQGCEDQWHSBAJP-TXICZTDVSA-N
9DG	F [auth A], J [auth C]	9-DEAZAGUANINE C6 H6 N4 O FFYPRJYSJODFFD-UHFFFAOYSA-N
MG	C [auth A], D [auth A], G [auth C], H [auth C]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
9DG	IC50:  9500   nM  Binding MOAD
9DG	IC50 :  9500   nM  PDBBind

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.05 Å
• R-Value Free: 0.154 
• R-Value Work: 0.122 
• Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 69.33	α = 90
b = 90.18	β = 90
c = 75.72	γ = 90

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
AMoRE	phasing
SHELXL-97	refinement
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2000-09-08 
• Released Date: 2000-12-06 
Deposition Author(s): Heroux, A., White, E.L., Ross, L.J., Kuzin, A.P., Borhani, D.W.

Revision History  

• Version 1.0: 2000-12-06
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Source and taxonomy, Version format compliance
• Version 1.3: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Data collection, Derived calculations, Structure summary