【摘要】 结合苏芸金杆菌不同品系毒力差异,对伴孢晶体形态、血清学特性进行了比较研究。对分属于7个血清型的19个株系的伴孢晶体观察表明:晶体形态以品系而异与分类属性无关;晶体可归为五个类型:菱形、嵌合形、球形、立方形、不规则形。发现具有嵌合形多的菌株对鳞翅目幼虫毒力不仅高,且在有毒力的菌株中嵌合形并不罕见;不规则形无毒力。对毒力差异大的菌株采用密度梯度离心提纯了其伴孢晶体,进行双向琼脂糖免疫扩散试验,证明了晶体形态与其对昆虫的毒力有关。更多还原

【Abstract】 An electromicroscopic examination of the shape of the parasporal crystals associated with 19 strains of B. thuringiensis is reported. It shows five types of parasporal crystals: bipyramidal, square, irregular, embedded, sphaeroid. It is first showed that the atoxigenic parasporal crystals of B. thuringiensis subsp, ostriniae (006) are of an irregular type.An explanation of the relation between the toxicity and shape of crystal is proposed. This conclusion is supported by the agarose double diffusion patterns obtained when antigen reacts with antiserum prepared from pure crystals (by usirg isopycnic centrifugation) of four strains of B. thuringiensis.更多还原