2K2S

structure of the MIC1-GLD/MIC6-EGF complex from Toxoplasma gondii

Summary for 2K2S

• Entry DOI: 10.2210/pdb2k2s/pdb
• Related: 2K2T
• Descriptor: Micronemal protein 1, Micronemal protein 6 (2 entities in total)
• Functional Keywords: microneme protein complex, cell adhesion, cytoplasmic vesicle, lectin, virulence, egf-like domain, membrane, transmembrane
• Biological source: Toxoplasma gondii; More
• Cellular location: Cytoplasmic vesicle, secretory vesicle, microneme: O00834; Cytoplasmic vesicle, secretory vesicle, microneme membrane; Single-pass type I membrane protein: Q9XYH7
• Total number of polymer chains: 2
• Total formula weight: 20325.55

Authors

Matthews, S. (deposition date: 2008-04-11, release date: 2009-02-24, Last modification date: 2024-10-16)

Primary citation

Sawmynaden, K.,Saouros, S.,Friedrich, N.,Marchant, J.,Simpson, P.,Bleijlevens, B.,Blackman, M.J.,Soldati-Favre, D.,Matthews, S.
Structural insights into microneme protein assembly reveal a new mode of EGF domain recognition
Embo Rep., 9:1149-1155, 2008

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. Adhesive complexes composed of microneme proteins (MICs) are secreted onto the parasite surface from intracellular stores and fulfil crucial roles in host-cell recognition, attachment and penetration. Here, we report the high-resolution solution structure of a complex between two crucial MICs, TgMIC6 and TgMIC1. Furthermore, we identify two analogous interaction sites within separate epidermal growth factor-like (EGF) domains of TgMIC6-EGF2 and EGF3-and confirm that both interactions are functional for the recognition of host cell receptor in the parasite, using immunofluorescence and invasion assays. The nature of this new mode of recognition of the EGF domain and its abundance in apicomplexan surface proteins suggest a more generalized means of constructing functional assemblies by using EGF domains with highly specific receptor-binding properties.

PubMed: 18818666
DOI: 10.1038/embor.2008.179

Experimental method

SOLUTION NMR