Optimization of the expression of surface antigen SAG1/2 of Toxoplasma gondii in the yeast Pichia pastoris
- Author:
Thiruvengadam, G.
;
Init, I.
;
Fong, M.Y.
;
Lau, Y.L.*
- Publication Type:Journal Article
- From:Tropical Biomedicine
2011;28(3):506-513
- CountryMalaysia
- Language:English
-
Abstract:
Surface antigens are the most abundant proteins found on the surface of the
parasite Toxoplasma gondii. Surface antigen 1 (SAG1) and Surface antigen 2 (SAG2) remain
the most important and extensively studied surface proteins. These antigens have been
identified to play a role in host cell invasion, immune modulation, virulence attenuation.
Recombinant SAG1/2 was cloned and expressed in yeast Pichia pastoris. We describe here
optimization of critical parameters involved in high yield expression of the recombinant
SAG1/2. Our results suggest that recombinant SAG1/2 were best expressed at 30ºC, pH 6 and
1% methanol as the carbon source by X33 Pichia cells. Additional optimizations included the
downstream process such as ammonium sulphate precipitation and dialysis. The fusion protein
was purified using Ni-NTA purification system with 80% recovery. The purified protein was
100% specific and sensitive in detection of toxoplasmosis.
- Full text:W020150615385841686851.pdf
