1KZQ

crystal structure of a parasite protein

Summary for 1KZQ

• Entry DOI: 10.2210/pdb1kzq/pdb
• Descriptor: Major Surface Antigen P30 (2 entities in total)
• Functional Keywords: sag1, major surface antigen, toxoplasma gondii, parasite invasion, mad, immune system
• Biological source: Toxoplasma gondii
• Cellular location: Parasitophorous vacuole: P13664
• Total number of polymer chains: 2
• Total formula weight: 59659.75

Authors

He, X.,Grigg, M.E.,Boothroyd, J.C.,Garcia, K.C. (deposition date: 2002-02-07, release date: 2002-07-31, Last modification date: 2024-10-09)

Primary citation

He, X.L.,Grigg, M.E.,Boothroyd, J.C.,Garcia, K.C.
Structure of the immunodominant surface antigen from the Toxoplasma gondii SRS superfamily.
Nat.Struct.Biol., 9:606-611, 2002

PubMed Abstract: Toxoplasma gondii is a persistent protozoan parasite capable of infecting almost any warm-blooded vertebrate. The surface of Toxoplasma is coated with a family of developmentally regulated glycosylphosphatidylinositol (GPI)-linked proteins (SRSs), of which SAG1 is the prototypic member. SRS proteins mediate attachment to host cells and interface with the host immune response to regulate the virulence of the parasite. The 1.7 A structure of the immunodominant SAG1 antigen reveals a homodimeric configuration in which the dimeric interface is mediated by an extended beta-sheet that forms a deep groove lined with positively charged amino acids. This basic groove seems to be conserved among SRS proteins and potentially serves as a sulfated proteoglycan-binding site on target cell surfaces, thus rationalizing the promiscuous attachment properties of Toxoplasma to a broad range of host cell types.

PubMed: 12091874

Experimental method

X-RAY DIFFRACTION (1.7 Å)