源于地衣的苏云金芽孢杆菌分离及PCR-RFLP分析

Natural Occurrence of Bacillus thuringiensis in Iichens and Identification with PCR-RFLP

以非维管植物地衣为分离材料,采用热处理加抗生素及醋酸钠的方法,经常规形态学鉴定,分离到6株苏云金芽孢杆菌.为了解其生物学特性,分别对这6株菌株进行生理生化测定和cry基因的PCR-RFLP检测,结果显示:6个菌株均含有cry1、cry1I、cry2基因,所有菌株均不含cry3、cry4、cry5、cry6、cry8、cry10、cry11基因.初步确定6株菌株中含有5种cry1亚类基因(cry1Ad,cry1Ba,cry1Cb,cry1Da,cry1Ea),1种cry2亚类基因cry2Ac,2种cry1I基因亚类(cry1Ia1、cry1Ib1),其中有2个菌株的PCR-RFLP图谱均出现特异性片段,推测可能存在新基因.

With heat treatment and selective culture medium which was developed through different concentrations and ratios of antibiotics and NaAc, under routine morphologic identification, 6 novel Bacillus thuringiensis strains has been isolated from lichen samples which is a kind of non-vascular plants. Physiological and biochemical reaction were tested for their biological characters. The PCR-PFLR technique was used to detect the contents of Bacillus thuringiensis genes. The results showed that cry1, cry1I and cry2 existed in all of the 6 strains, meanwhile, no cry3, cry4, cry5, cry6, cry8, cry10 and cry11 genes were detected. Five kinds of sub-genes of cry1 were detected in the strains which were cry1Ad, cry1Ba, cry1Cb, cry1Da and crylEa, only one sub-gene of cry2 named cry2Ac was detected, cry1Ia1 and cry1Ib1 as sub-genes of cry1I were found in the 6 novel strains. Some special DNA fragments which were detected from 2 of the strains inferred to the existence of new genes.