Kronstad J W, Whiteley H R
J Bacteriol. 1984 Oct;160(1):95-102. doi: 10.1128/jb.160.1.95-102.1984.
Two sets of inverted repeat DNA sequences, IR2150 and IR1750, were discovered flanking the crystal protein gene on the 75-kilobase plasmid of Bacillus thuringiensis subsp. kurstaki HD73. A restriction map of ca. 40 kilobases around the crystal protein gene was constructed, and the positions of the copies of IR2150 and IR1750 were determined. Three copies of IR2150 were found flanking the crystal protein gene in an inverted orientation, and one partial and three intact copies of IR1750 were found in both inverted and direct orientations around the gene. Hybridization experiments with fragments from within IR2150 and IR1750 demonstrated the presence of multiple copies of these sequences on the chromosome of B. thuringiensis subsp. kurstaki HD73 and also revealed a strong correlation between the presence of these sequences and the presence of the crystal protein gene on plasmids from 14 strains of B. thuringiensis.
在苏云金芽孢杆菌库斯塔克亚种HD73的75千碱基质粒上，发现两组反向重复DNA序列IR2150和IR1750位于晶体蛋白基因两侧。构建了晶体蛋白基因周围约40千碱基的限制酶切图谱，并确定了IR2150和IR1750拷贝的位置。发现三个IR2150拷贝以反向排列位于晶体蛋白基因两侧，并且在该基因周围发现了一个部分拷贝和三个完整拷贝的IR1750，它们既有反向排列也有正向排列。用IR2150和IR1750内部的片段进行杂交实验，证明了这些序列在苏云金芽孢杆菌库斯塔克亚种HD73染色体上存在多个拷贝，同时也揭示了这些序列的存在与来自14株苏云金芽孢杆菌质粒上晶体蛋白基因的存在之间存在很强的相关性。
