Abstract:  In order to study the structure and function of Glutaminyl-tRNA Synthetase,we synthesise the Glutaminyl-tRNA Synthetase and -tRNA^Glngene, then the gene was subcloned into expression vector PET-28a-His-GlnRS and PIDTpSMART,separately , expessed Glutaminyl-tRNA Synthetase protein in BL21(DE3) by IPTG induction and we determined the activity of purify Glutaminyl-tRNA Synthetase Results showed that the Glutaminyl-tRNA Synthetase protein had been successfully expressed in E.coli. The substrate glutamine do not inhibit the activity of Glutaminyl-tRNA Synthetase.

Key words: Glutaminyl-tRNA Synthetase; Prokaryotic expression, Enzyme activity