Abstract:

Cathepsin B from Helicoverpa armigera (HCB) plays important role in the life of the cotton bollworm, which degrades yolk proteins to amino acids as nutrients for embryonic development. Many plant seeds, such as soybean seeds and sunflower seeds, contain proteinase inhibitors. An inhibitor, HCB-SoyI, purified from the soybean seeds by ammonium sulfate precipitation, gel filtration and ion-exchange chromatography, was here reported. The inhibitory activity of the inhibitor was further studied with bovine albumin as a substrate. The purified inhibitor offers an opportunity to further clone its gene and may become a new target for insect resistant transgenic plant research.

Key words: Helicoverpa armigera, soybean seeds, cathepsin B, inhibitor, purification