Sohail M, Oldridge M, Dyke K G
Department of Biochemistry, University of Oxford, UK.
FEMS Microbiol Lett. 1995 Apr 1;127(3):165-70. doi: 10.1111/j.1574-6968.1995.tb07468.x.
The plasmid pI9789::Tn552 carries genes conferring resistance to penicillins and to cadmium, mercury and arsenate ions. The presence of Tn551 at one location in the chromosome of Staphylococcus aureus enhances the frequency of suppression of thermosensitivity of replication of the plasmids pS1 and p delta D which are derivatives of pI9789::Tn552. Bacteriophage propagated on the bacteria in which thermosensitivity of replication had been suppressed was used to transduce cadmium resistance to S. aureus PS80N. The cadmium-resistant transductants obtained carried plasmid pS1 or p delta D with a copy of Tn551 inserted into a specific site on pS1 but into several different sites on p delta D. The possible mechanisms of the suppression are discussed.
质粒pI9789::Tn552携带赋予对青霉素以及镉离子、汞离子和砷酸根离子抗性的基因。金黄色葡萄球菌染色体中某一位置上Tn551的存在提高了对pS1和pδD质粒复制热敏感性抑制的频率,pS1和pδD是pI9789::Tn552的衍生物。在复制热敏感性已被抑制的细菌上繁殖的噬菌体被用于将镉抗性转导至金黄色葡萄球菌PS80N。获得的抗镉转导子携带质粒pS1或pδD,其中有一个Tn551拷贝插入到pS1的特定位点,但插入到pδD的几个不同位点。文中讨论了抑制的可能机制。