Yasutake Koichi, Binh Ngo Dinh, Kagoshima Kumiko, Uemori Akiko, Ohgushi Akira, Maeda Minoru, Mizuki Eiichi, Yu Yong Man, Ohba Michio
Graduate School of Agriculture, Kyushu University, Fukuoka, Japan.
Can J Microbiol. 2006 Apr;52(4):365-72. doi: 10.1139/w05-134.
A total of 63 Bacillus thuringiensis isolates were recovered from urban soils of Hanoi, Vietnam. Of these, 34 were identified to 12 H serogroups. None of the isolates showed larvicidal activities against three lepidopterous insects. Three isolates belonging to the two serovars, colmeri (H21) and konkukian (H34), were highly toxic to larvae of the mosquito Aedes aegypti. Parasporal inclusion proteins of four isolates exhibited cytocidal activities against HeLa cells. Immunologically, proteins of four isolates were closely related to parasporin-1 (Cry31Aa), a parasporal protein that preferentially kills human cancer cells. Haemolytic activities were associated with parasporal proteins of the three mosquitocidal isolates but not with those of the four cancer-cell-killing isolates. PCR experiments and nucleotide sequence analysis revealed that the genes of four anti-cancer isolates are closely related to the gene parasporin-1 (cry31Aa) but are dissimilar to those of the three other existing parasporins. Our results suggest that the soil of northern Vietnam is a good reservoir of parasporin-producing B. thuringiensis.
从越南河内的城市土壤中总共分离出63株苏云金芽孢杆菌。其中，34株被鉴定为12个H血清群。所有分离株对三种鳞翅目昆虫均未表现出杀幼虫活性。属于两个血清型，即科尔梅里（H21）和康库基安（H34）的三株分离株对埃及伊蚊幼虫具有高毒性。四株分离株的伴孢晶体蛋白对HeLa细胞表现出杀细胞活性。在免疫学上，四株分离株的蛋白与伴孢蛋白-1（Cry31Aa）密切相关，伴孢蛋白-1是一种优先杀死人类癌细胞的伴孢蛋白。溶血活性与三株杀蚊分离株的伴孢蛋白有关，但与四株杀癌细胞分离株的伴孢蛋白无关。PCR实验和核苷酸序列分析表明，四株抗癌分离株的基因与伴孢蛋白-1（cry31Aa）基因密切相关，但与其他三种现有伴孢蛋白的基因不同。我们的结果表明，越南北部的土壤是产生伴孢蛋白的苏云金芽孢杆菌的良好储存库。
