Isolation and Characterization of Heat Shock Protein 70-Ipek 1 from Toxoplasma gondii

Abstract

Toxoplasma gondii is a common intracellular parasite that causes the toxoplasmosis. Heat shock proteins (Hsps) have a critical role in pathogenesis of toxoplasmosis. Hsps are highly conserved proteins in evolution among living organisms. This protein family responsible for a wide range of biological processes such as protein folding, protein translocation, protein aggregation. In the present study, Hsp70, a member of the Hsp family, was isolated from T. gondii and its sequence and motifs were determined by PCR, cloning, sequencing and homology modelling analysis. ATP hydrolysis, luciferase folding, and luciferase aggregation experiments were performed for determination of its chaperone activity while the stability and secondary structure of the Hsp70 were discovered by using biophysical experiments (FTIR, florescence and quenching experiment). In addition, in silico analysis were used to determine the physicochemical characteristics of Hsp70. The results revealed that Hsp70 protein obtained from T. gondii (Hsp70-IPEK1) is similar to Hsp70s from other organisms. Also, the chaperone activity, stability and secondary structure of Hsp70-IPEK1 were determined. Hsp70-IPEK1 together with other chaperones in the presence of nucleotide were dramatically increased protein folding and aggregation. According to these results, it is thought that Hsp70 has a potential to contribute many research areas such as pharmaceutical analysis