Recombinant Dense Granular Protein (GRA5) for Detection of Human Toxoplasmosis by Western Blot

Figure 1

SDS-PAGE analysis on the optimized expression of rGRA5 protein in E. coli BL21 pLysS (DE3), Coomassie blue stained. Lane 5: prestained broad range protein marker. Lane 1, cell pellet fractions of pRSET B clone as negative control before induction (0 hr). Lane 2: cell pellet fractions of pRSET B clone after induction with 0.5 mM IPTG (4 hr). Lanes 3 to 4: cell pellet fractions of pRSET B clone after induction with 1.0 mM IPTG (2, 4 hr). Lane 6: cell pellet fractions of GRA5 clone before induction (0 hr). Lanes 7 to 8: cell pellet fractions of GRA5 clone after induction with 0.5 mM IPTG (2, 4 hr). Lanes 9 to 10: cell pellet fractions of GRA5 clone after induction with 1.0 mM IPTG (2, 4 hr). The GRA5 protein band of interest was observed at molecular weight of 20 kDa (arrow) compared to the negative control. The band intensity increased from 0 to 2 hr after induction and remained constant at the 4th hr with 1.0 mM IPTG, the optimum condition for maximum expression of the protein.