Hartskeerl R A, Hoekstra W P
Antonie Van Leeuwenhoek. 1984;50(2):113-24. doi: 10.1007/BF00400171.
The stage at which exclusion operates in matings between donors belonging to the I-type incompatibility group (IncI) was investigated. Mating between Escherichia coli cells harbouring the I-type plasmid R144 and E. coli cells harbouring the R144-derived recombinant plasmid pRAH308, which causes a hundredfold exclusion, was performed on a membrane filter to test whether mating aggregate formation was disturbed. Besides, level and kinetics of the formation of mating aggregates in mixtures of R144+ donor cells and recipient cells carrying plasmid pRAH308 (exclusion-proficient) was compared with the aggregate formation in mixtures of the donor cells and exclusion-deficient recipient cells. Results from these experiments revealed that the exclusion by pRAH308 does not operate at the level of aggregate formation, but acts at the stage of DNA transfer. The exclusion phenomenon by the recombinant plasmid pRAH308 appeared to be representative for exclusion caused by plasmid R144, since essentially identical results were obtained if plasmid R144 was used as exclusion-determining factor.
对属于I型不相容组（IncI）的供体之间交配时排斥作用发生的阶段进行了研究。在膜滤器上进行了携带I型质粒R144的大肠杆菌细胞与携带R144衍生重组质粒pRAH308（引起百倍排斥）的大肠杆菌细胞之间的交配，以测试交配聚集体的形成是否受到干扰。此外，将R144 +供体细胞与携带质粒pRAH308（具有排斥能力）的受体细胞混合物中交配聚集体形成的水平和动力学与供体细胞和缺乏排斥能力的受体细胞混合物中的聚集体形成进行了比较。这些实验的结果表明，pRAH308引起的排斥作用不是在聚集体形成水平上起作用，而是在DNA转移阶段起作用。重组质粒pRAH308引起的排斥现象似乎代表了质粒R144引起的排斥，因为如果使用质粒R144作为排斥决定因素，会得到基本相同的结果。
