关键词: 亚洲玉米螟, 血清, 酚氧化酶原, 分子量, 最适pH, 最适温度, 酶活性

Abstract:

The prophenoloxidase (PPO) was purified from the hemolymph of the larvae of Ostrinia furnacalis (Guenée) by sequential use of precipitation in 40% saturation ammonium sulfate, the affinity chromatography of Blue Sepharose CL-6B and Phenyl Sepharose CL-4B. The relative molecular weight of prophenoloxidase was 158 kD, and the molecular weight of two subunits was 80 kD and 78 kD, respectively. The prophenoloxidase was glycoprotein and could be activated by 0.1 mmol/L cetylpyridmium chloride (CPC), 50% methanol, 1 mg/mL laminarin and 1 mg/mL trypsin. The optimum pH was 7.0 and the optimum temperature 25-30℃ for prophenoloxidase activity, which could be significantly stimulated by Mg²⁺ and Ca^2+.

Key words: Ostrinia furnacalis, serum, prophenoloxidase, molecular weight, optimum pH, optimum temperature, enzyme activity