Aronson A I, Beckman W
Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907.
Appl Environ Microbiol. 1987 Jul;53(7):1525-30. doi: 10.1128/aem.53.7.1525-1530.1987.
A low frequency of chromosomal gene transfer from Bacillus thuringiensis to Bacillus cereus was detected by cell mating, with a tryptophan marker being the most frequently transferred gene among four that were tested. The process was resistant to DNase and was not mediated by cell filtrates. Among several B. thuringiensis subspecies tested, transfer was best with a derivative of B. thuringiensis subsp. kurstaki HD1, which lost several plasmids. All of the B. cereus recombinants contained at least one plasmid from the donor B. thuringiensis; frequently, it was a plasmid that encoded a protoxin gene. In matings with B. thuringiensis subsp. kurstaki HD1, a 29-megadalton plasmid that contained a ca. 2.5-kilobase region of homology with the chromosome was always transferred. No detectable transfer of chromosomal genes was found in B. thuringiensis subsp. kurstaki HD1 strains lacking this plasmid, suggesting that there may be chromosome mobilization.
通过细胞交配检测到苏云金芽孢杆菌向蜡状芽孢杆菌的染色体基因转移频率较低，在测试的四个基因中，色氨酸标记基因是最常转移的基因。该过程对脱氧核糖核酸酶具有抗性，且不受细胞滤液介导。在测试的几个苏云金芽孢杆菌亚种中，苏云金芽孢杆菌库斯塔克亚种HD1的一个衍生物转移效果最佳，该衍生物丢失了几个质粒。所有蜡状芽孢杆菌重组体都至少含有一个来自供体苏云金芽孢杆菌的质粒；通常，它是一个编码原毒素基因的质粒。在与苏云金芽孢杆菌库斯塔克亚种HD1交配时，一个29兆道尔顿的质粒总是被转移，该质粒含有一个与染色体约2.5千碱基的同源区域。在缺乏该质粒的苏云金芽孢杆菌库斯塔克亚种HD1菌株中未发现可检测到的染色体基因转移，这表明可能存在染色体动员。
