1FSG

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

• PDB DOI: https://doi.org/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 

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,PQS (software)

Macromolecule Content

• Total Structure Weight: 54.59 kDa 
• Atom Count: 4,860 
• Modelled Residue Count: 466 
• Deposited Residue Count: 466 
• Unique protein chains: 1

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
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

Binding Affinity Annotations
ID	Source	Binding Affinity
9DG	PDBBind:  1FSG	IC50: 9500 (nM) from 1 assay(s)
	Binding MOAD:  1FSG	IC50: 9500 (nM) from 1 assay(s)

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

• 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
• Version 1.4: 2024-02-07
  Changes: Data collection, Database references, Structure summary
• Version 1.5: 2024-04-03
  Changes: Refinement description