Sox T E, Mohammed W, Blackman E, Biswas G, Sparling P F
J Bacteriol. 1978 Apr;134(1):278-86. doi: 10.1128/jb.134.1.278-286.1978.
A conjugation system initially discovered in beta-lactamase-producing gonococci mobilized small non-selftransmissible R plasmids encoding beta-lactamase (penicillinase) production into other gonococci, Neisseria, and Escherichia coli. This conjugation system was mediated by a separate selftransmissible plasmid of 23.9 X 10(6) daltons, pFA2. Conjugative plasmids capable of mobilizing R plasmids were also found in nearly 8% of the non-penicillinase-producing gonococci. These were similar to pFA2 in size, buoyant density, and restriction endonuclease digest patterns but were less efficient than pFA2 in mobilization of the penicillinase plasmid pFA3. The presence of conjugative plasmids in gonococci isolated before the appearance of penicillinase-producing strains indicates that a conjugation system for plasmid transfer predated the appearance of R plasmids in gonococci.
最初在产β-内酰胺酶的淋球菌中发现的一种接合系统，可将编码β-内酰胺酶（青霉素酶）产生的小型非自我传递R质粒转移到其他淋球菌、奈瑟菌和大肠杆菌中。这种接合系统由一个23.9×10⁶道尔顿的独立自我传递质粒pFA2介导。在近8%的不产青霉素酶的淋球菌中也发现了能够转移R质粒的接合质粒。这些接合质粒在大小、浮力密度和限制性内切酶消化模式上与pFA2相似，但在转移青霉素酶质粒pFA3方面比pFA2效率低。在产青霉素酶菌株出现之前分离的淋球菌中存在接合质粒，这表明质粒转移的接合系统在淋球菌中R质粒出现之前就已存在。
