2JH1 | pdb_00002jh1

Crystal structure of Toxoplasma gondii micronemal protein 1

• PDB DOI: https://doi.org/10.2210/pdb2JH1/pdb

• Classification: CELL ADHESION
• Organism(s): Toxoplasma gondii
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2007-02-19 Released: 2007-05-22 
• Deposition Author(s): Blumenschein, T.M.A., Friedrich, N., Childs, R.A., Saouros, S., Carpenter, E.P., Campanero-Rhodes, M.A., Simpson, P., Koutroukides, T., Blackman, M.J., Feizi, T., Soldati-Favre, D., Matthews, S.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 
  0.205 (Depositor), 0.204 (DCC) 
• R-Value Work: 
  0.178 (Depositor), 0.176 (DCC) 
• R-Value Observed: 
  0.179 (Depositor) 

Literature

Atomic Resolution Insight Into Host Cell Recognition by Toxoplasma Gondii.

Blumenschein, T.M.A., Friedrich, N., Childs, R.A., Saouros, S., Carpenter, E.P., Campanero-Rhodes, M.A., Simpson, P., Chai, W., Koutroukides, T., Blackman, M.J., Feizi, T., Soldati-Favre, D., Matthews, S.

(2007) EMBO J 26: 2808

• PubMed: 17491595 
• DOI: https://doi.org/10.1038/sj.emboj.7601704
• Primary Citation Related Structures: 
  2JH1, 2JH7, 2JHD


• PubMed Abstract: 
  

  The obligate intracellular parasite Toxoplasma gondii, a member of the phylum Apicomplexa that includes Plasmodium spp., is one of the most widespread parasites and the causative agent of toxoplasmosis. Micronemal proteins (MICs) are released onto the parasite surface just before invasion of host cells and play important roles in host cell recognition, attachment and penetration. Here, we report the atomic structure for a key MIC, TgMIC1, and reveal a novel cell-binding motif called the microneme adhesive repeat (MAR). Using glycoarray analyses, we identified a novel interaction with sialylated oligosaccharides that resolves several prevailing misconceptions concerning TgMIC1. Structural studies of various complexes between TgMIC1 and sialylated oligosaccharides provide high-resolution insights into the recognition of sialylated oligosaccharides by a parasite surface protein. We observe that MAR domains exist in tandem repeats, which provide a highly specialized structure for glycan discrimination. Our work uncovers new features of parasite-receptor interactions at the early stages of host cell invasion, which will assist the design of new therapeutic strategies.

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Organizational Affiliation: 
• Division of Molecular Biosciences, Imperial College London, London, UK.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

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

Macromolecule Content 

• Total Structure Weight: 28.31 kDa 
• Atom Count: 2,094 
• Modeled Residue Count: 235 
• Deposited Residue Count: 246 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
MICRONEMAL PROTEIN 1	A	246	Toxoplasma gondii	Mutation(s): 0
UniProt
Find proteins for O00834 (Toxoplasma gondii) Explore O00834  Go to UniProtKB:  O00834

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
GOL	O [auth A], T [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
ACT	B [auth A], C [auth A], D [auth A], E [auth A], F [auth A], G [auth A], H [auth A], I [auth A], J [auth A], K [auth A], L [auth A], P [auth A], Q [auth A], R [auth A], S [auth A]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M
CL	M [auth A], N [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free:  0.205 (Depositor), 0.204 (DCC) 
• R-Value Work:  0.178 (Depositor), 0.176 (DCC) 
• R-Value Observed: 0.179 (Depositor) 

Space Group: P 4₃ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 66.192	α = 90
b = 66.192	β = 90
c = 172.299	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling
SOLVE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2007-05-22 
Deposition Author(s): Blumenschein, T.M.A., Friedrich, N., Childs, R.A., Saouros, S., Carpenter, E.P., Campanero-Rhodes, M.A., Simpson, P., Koutroukides, T., Blackman, M.J., Feizi, T., Soldati-Favre, D., Matthews, S.

Revision History  

• Version 1.0: 2007-05-22
  Type: Initial release
  
• Version 1.1: 2011-05-08
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2019-01-30
  Changes: Data collection, Derived calculations, Experimental preparation, Other
• Version 1.4: 2024-10-16
  Changes: Data collection, Database references, Derived calculations, Other, Structure summary