Baldi M I, Benedetti P, Mattoccia E, Tocchini-Valentini G P
Cell. 1980 Jun;20(2):461-7. doi: 10.1016/0092-8674(80)90632-7.
Extracts from X. laevis germinal vesicles interlock duplex DNA circles to form catenanes. The catenation activity requires Mg++ and ATP. Negatively supercoiled or relaxed DNA can be used as substrates for the catenation reaction. Homology between donor and acceptor DNA is not required, since catenanes are formed between DNA molecules with unrelated sequences. In the course of the isolation of the activity responsible for the catenation reaction, we discovered a new ATP-dependent topoisomerase. The fractions containing the novel topoisomerase catenate and decatenate DNA, the ionic strength dictating which of the two opposing reactions will occur.
非洲爪蟾生发泡提取物可使双链DNA环互锁形成连环体。连环化活性需要Mg++和ATP。负超螺旋或松弛的DNA均可作为连环化反应的底物。供体DNA与受体DNA之间不需要同源性，因为连环体是在具有不相关序列的DNA分子之间形成的。在分离负责连环化反应的活性过程中，我们发现了一种新的ATP依赖性拓扑异构酶。含有这种新型拓扑异构酶的组分可使DNA连环化和解连环化，离子强度决定两种相反反应中会发生哪一种。
