Abstract: The intact open reading fragment sequence of mature GOBP2-Harm from Helicoverpa armigera was obtained by PCR amplification. The ORF of GOBP2-Harm was subcloned into expression vector pGEX-4T-1. Recombinant protein was expressed successfully in E. coli induced by IPTG. The analysis of SDS-PAGE showed that most of recombinant protein was insoluble inclusion body and only little fraction of recombinant protein of GOBP2-Harm is soluble. In order to obtain abundant soluble recombinant protein, the insoluble inclusion body GOBP2-Harm was solubilized, refolded and purified. The purified product was crossreactive with an anti-GOBP (Antheraea polyphemus) antiserum, which indicated the purified protein belonged to GOBP of insect.

Key words: Helicoverpa armigera, general odorant binding proteinⅡ, PCR amplification, prokaryotic expression, recombinant protein, affinity chromatography