Sanchis V, Lereclus D, Menou G, Chaufaux J, Lecadet M M
Unité de Biochimie Microbienne, Institut Pasteur, Paris, France.
Mol Microbiol. 1988 May;2(3):393-404. doi: 10.1111/j.1365-2958.1988.tb00044.x.
The hypothesis according to which multiple and different delta-endotoxin genes could determine the host-range specificity of the lepidopteran strains of Bacillus thuringiensis is being checked in the case of strains aizawai 7.29 (serotype 7) and entomocidus 601 (serotype 6). From these strains, several crystal protein genes, belonging to different structural types, have been isolated. One of the cloned genes that is not present in strain entomocidus 601 is duplicated in strain aizawai 7.29. This gene belongs to a previously characterized type of crystal protein gene and encodes a protein preferentially active against Pieris brassicae. Two other genes, of presumed chromosomal location, are present in both strains and each displays a unique physical map. In both strains the two genes are in close proximity and in the same orientation. The first, which belongs to a new type of crystal protein gene, encodes a 130-140 kD protein that is not significantly active against the two insect species tested. The other new type of crystal protein gene directs the synthesis of a polypeptide preferentially active against Spodoptera littoralis.
关于多种不同的δ-内毒素基因可决定苏云金芽孢杆菌鳞翅目菌株宿主范围特异性的假说，正在苏云金芽孢杆菌 aizawai 7.29（血清型 7）和 entomocidus 601（血清型 6）菌株的研究中得到验证。从这些菌株中，已分离出几种属于不同结构类型的晶体蛋白基因。在菌株 entomocidus 601 中不存在的一个克隆基因，在菌株 aizawai 7.29 中是重复的。该基因属于先前已鉴定的一种晶体蛋白基因类型，编码一种对菜青虫具有优先活性的蛋白质。另外两个推测位于染色体上的基因，在两种菌株中均存在，且各自呈现独特的物理图谱。在两种菌株中，这两个基因都紧密相邻且方向相同。第一个基因属于一种新型晶体蛋白基因，编码一种 130 - 140 kD 的蛋白质，对所测试的两种昆虫物种没有显著活性。另一种新型晶体蛋白基因指导合成一种对斜纹夜蛾具有优先活性的多肽。
