苏云金芽孢杆菌科默尔亚种15A3株的cry基因分析及杀虫特性

筛选的苏云金芽孢杆菌野生菌株15A3经鉴定属血清H21型科默尔亚种。用PCR及RFLP方法对其cry1类基因分析证明其含有cry1Aa,\%cry1\%Ac,\%cry1\%Ca,\%cry1\%D,\%cry1\%I及cry2六种cry基因，其cry1A基因N末端145kb片段与已发表的序列有差异。表达晶体蛋白质的分子量分别为130，79，70，65，51和45kD。对家蝇致畸实验证明其不含β外毒素。发酵液对棉铃虫，甜菜夜蛾，小菜蛾及美国白蛾均具较高的毒力。证明野生的苏云金芽孢杆菌资源中也有具国外工程菌所特有的高效杀虫晶体蛋白基因组合的优良菌株。

Characterization of cry Gene and Broad Spectrum Against Lepidopteran of Bacillus thuringiensis subsp. colmeri 15A3

Bacillus thuringiensis wild type strain 15A3 belongs to subspecies colmeri serotype H-21. RFLP and PCR analysis show that it contains six types of ICP genes: cry1Aa, cry1Ac, cry1Ca, cry1D, cry1I and cry. The sequence of the 1.45 kb N-terminal fragment of cry1Aa differed from that of published. SDS-PAGE showed that the crystal consists of proteins with molecular weight about 130, 79, 70, 65, 51 and 45 kD. Strain 15A3 didn't sysnthesize heat-stable beta-exotoxins according to test of house fly aberration. The 1.2 tons fermentative production exhibited high toxicity against three lepidopteran pests: H. armigera, S. exigua and H. cunea. It was proved that wild type strain can produce a broad specturm of ICP.