Li M S, Je Y H, Lee I H, Chang J H, Roh J Y, Kim H S, Oh H W, Boo K S
School of Agricultural Biotechnology, Seoul National University, 103 Seodoon-Dong, Suwon 441-744, Korea.
Curr Microbiol. 2002 Oct;45(4):299-302. doi: 10.1007/s00284-002-3755-0.
A strain of Bacillus thuringiensis that showed significantly high toxicity to Plutella xylostella and Spodoptera exigua was isolated from a Korean soil sample and characterized. The isolate, named B. thuringiensis K1, was determined to belong to ssp. kurstaki (H3a3b3c) type by an H antisera agglutination test and produced bipyramidal inclusions. Plasmid pattern of K1 was different from that of the reference strain, ssp. kurstaki HD-1, but the parasporal inclusion protein profile of K1 had two major bands that were similar in size to those of ssp. kurstaki HD-1. To verify the delta-endotoxin gene types of K1, PCR analysis with specific cry gene primers was performed to show that K1 contained a new cry gene in addition to cry1Aa, cry1Ab, cry1Ac, cry1E and cry2 genes. PCR-amplified region of the new cry gene, cryX, showed 79% similarity to cry1Fa1 gene (GenBank Accession No. M63897). In an insect toxicity assay, K1 had higher toxicity against Plutella xylostella and S. exigua than ssp. kurstaki HD-1.
从韩国土壤样本中分离出了一株对小菜蛾和甜菜夜蛾具有显著高毒性的苏云金芽孢杆菌菌株，并对其进行了表征。该分离株名为苏云金芽孢杆菌K1，通过H抗血清凝集试验确定其属于库尔斯塔克亚种（H3a3b3c）类型，并产生双金字塔形内含物。K1的质粒图谱与参考菌株库尔斯塔克亚种HD-1不同，但K1的伴孢晶体蛋白图谱有两条主要条带，其大小与库尔斯塔克亚种HD-1的相似。为了验证K1的δ-内毒素基因类型，使用特定的cry基因引物进行PCR分析，结果表明K1除了含有cry1Aa、cry1Ab、cry1Ac、cry1E和cry2基因外，还含有一个新的cry基因。新cry基因cryX的PCR扩增区域与cry1Fa1基因（GenBank登录号M63897）显示出79%的相似性。在昆虫毒性试验中，K1对小菜蛾和甜菜夜蛾的毒性高于库尔斯塔克亚种HD-1。
