4APL

Crystal Structure of AMA1 from Neospora caninum


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.90 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.193 
  • R-Value Observed: 0.197 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Babesia Divergens and Neospora Caninum Apical Membrane Antigen 1 (Ama1) Structures Reveal Selectivity and Plasticity in Apicomplexan Parasite Host Cell Invasion.

Tonkin, M.L.Crawford, J.Lebrun, M.L.Boulanger, M.J.

(2013) Protein Sci 22: 114

  • DOI: https://doi.org/10.1002/pro.2193
  • Primary Citation of Related Structures:  
    4APL, 4APM

  • PubMed Abstract: 

    Host cell invasion by the obligate intracellular apicomplexan parasites, including Plasmodium (malaria) and Toxoplasma (toxoplasmosis), requires a step-wise mechanism unique among known host-pathogen interactions. A key step is the formation of the moving junction (MJ) complex, a circumferential constriction between the apical tip of the parasite and the host cell membrane that traverses in a posterior direction to enclose the parasite in a protective vacuole essential for intracellular survival. The leading model of MJ assembly proposes that Rhoptry Neck Protein 2 (RON2) is secreted into the host cell and integrated into the membrane where it serves as the receptor for apical membrane antigen 1 (AMA1) on the parasite surface. We have previously demonstrated that the AMA1-RON2 interaction is an effective target for inhibiting apicomplexan invasion. To better understand the AMA1-dependant molecular recognition events that promote invasion, including the significant AMA1-RON2 interaction, we present the structural characterization of AMA1 from the apicomplexan parasites Babesia divergens (BdAMA1) and Neospora caninum (NcAMA1) by X-ray crystallography. These studies offer intriguing structural insight into the RON2-binding surface groove in the AMA1 apical domain, which shows clear evidence for receptor-ligand co-evolution, and the hyper variability of the membrane proximal domain, which in Plasmodium is responsible for direct binding to erythrocytes. By incorporating the structural analysis of BdAMA1 and NcAMA1 with existing AMA1 structures and complexes we were able to define conserved pockets in the AMA1 apical groove that could be targeted for the design of broadly reactive therapeutics.


  • Organizational Affiliation

    Department of Biochemistry & Microbiology, University of Victoria, Victoria, British Columbia, V8W 3P6, Canada.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
APICAL MEMBRANE ANTIGEN 1A,
B,
C [auth D],
D [auth E]
431Neospora caninumMutation(s): 0 
UniProt
Find proteins for A2A114 (Neospora caninum)
Explore A2A114 
Go to UniProtKB:  A2A114
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA2A114
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.90 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.193 
  • R-Value Observed: 0.197 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 251.56α = 90
b = 51β = 90.93
c = 145.34γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
MOSFLMdata reduction
SCALAdata scaling
PHASERphasing

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2012-12-05
    Type: Initial release
  • Version 1.1: 2013-01-16
    Changes: Database references
  • Version 1.2: 2023-12-20
    Changes: Data collection, Database references, Other, Refinement description