Characterisation of a truncated Toxoplasma gondii surface antigen 2 (SAG2) secreted by the methylotrophic yeast Pichia pastoris.
A truncated form of surface antigen 2 (SAG2) of the protozoan parasite Toxoplasma gondii was cloned and expressed in the methylotrophic yeast Pichia pastoris. This recombinant antigen, designated as recSAG2-N, contained only the N-terminal half of the native SAG2. The recSAG2-N was secreted by the Pichia pastoris into the culture supernatant, and it was harvested by using the trichloroacetic acid precipitation method. Specificity of recSAG2-N was evaluated in western blot assays. Fifty human serum samples, including 32 from confirmed cases of toxoplasmosis, were tested. Results from the assays showed that recSAG2-N reacted with sera from the toxoplasmosis cases only. In vivo experiments showed that serum from mice which received recSAG2-N reacted with the native SAG2 of T. gondii.
Lau
Y L
YL
Department of Parasitology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Shamilah
Hisam
H
Fong
M Y
MY
D000595:Amino Acid Sequence; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D005260:Female; D006801:Humans; D051379:Mice; D010843:Pichia / Q000378:metabolism*; D015800:Protozoan Proteins / Q000378:metabolism*; D012698:Serologic Tests; D014122:Toxoplasma; D014123:Toxoplasmosis / Q000175:diagnosis
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D015800:Protozoan Proteins; C067547:surface antigen P22, Toxoplasma