EXPRESSION AND IDENTIFICATION OF NEWBORN LARVAE STAGE-SPECIFIC GENE T668 cDNA OF TRICHINELLA SPIRALIS IN ESCHERICHIA COLI

Objective To express and identify newborn larvae stage-specific T668 cDNA of Trichinella spiralis in Escherichia coli, so as to obtain genic engineer antigen. Methods T668 cDNA with no signal peptide sequence was obtained from pBK-CMV-T668 by PCR, and subcloned into prokaryotic expression vector pET28a (+), and the recombinant expression plasmid (pETT668) was constructed. Then, the expression plasmid was transformed into E. coli strain DE_~3 and induced by IPTG, the expressed protein was identified by SDS-PAGE. Results The molecular weight of the expressed protein was 49 ku, the quantity of the expressed protein increased with time extending and reached 34.6% of the total bacterial protein after inducing 5 hours. Western blotting showed the expressed protein was recognized by positive sera from swine infected with T. spiralis. Conclusion Newborn larvae stage-specific T668 cDNA of T. spiralis was expressed and identified, and the expressed protein had satisfactory antigenicity.