球形芽孢杆菌Ts-1毒蛋白的分离纯化

SEPARATION AND PURIFICATION OF THE TOXIC PROTEIN OF BACILLUS SPHAERICUS TS-1

球形芽孢杆菌 Ts-1对蚊虫幼虫有高效杀灭能力,其有毒成份为一种蛋白质。纯芽孢-晶体复合物经超声波处理后,以0.05mol/L 的 NaOH 抽提毒素,经 Sephadex G-200葡聚糖凝胶柱层析纯化,用 SDS-PAGE 检验柱层析得到的杀虫活性部分,Ts-1的芽孢-晶体复合物中主要为42kD 和43kD 的两种蛋白质。经聚丙烯酰胺凝胶制备电泳分离纯化,生物活性测定表明这两种蛋白质都有杀蚊毒效,经 DEAE 纤维素柱层析进一步纯化,获得了分子量为42kD的毒蛋白。

Bacillus sphaericus strain Ts-1 is highlyinsecticidal to larvae of the mosquito.It'sinsecticidal component is toxic proteins.Thetoxin was extracted from spore-crystal com-plexes by disruption in a Sonicator Cell Dis-ruptor Model W-220F followed by treatmentwith 0.05 mol/L NaOH.Fraction recoveredfrom chromatography of the spore-crystalcomplexes on column of Sephadex G-200 wereassayed against mosquito larvae and the toxicfractions from gel chromatography were su-bjected to SDS-PAGE.The toxic proteins inB.sphaericus Ts-1 spore-crystal complex mi-grated in position corresponding to 42kD and43kD.Bioassay of the two purified proteinsprepared by PAGE indicated that they wereall toxic to mosquito larvae.Toxic protein was further purified byDEAE-cellulose chromatography.The toxicprotein with a molecular weight of 42kD wasobtained.