Been M D, Burgess R R, Champoux J J
Biochim Biophys Acta. 1984 Jul 18;782(3):304-12. doi: 10.1016/0167-4781(84)90066-6.
Properties of strand breakage in duplex and single-stranded DNA by the wheat germ type 1 DNA topoisomerase were investigated. Strand breakage in duplex DNA is dependent upon the use of denaturing conditions to inactivate the enzyme and terminate the reaction, whereas breakage of single-stranded DNA occurs under the normal reaction conditions and is not dependent upon denaturation. Breakage generates a free 5' hydroxyl group and enzyme bound to the 3' side of the break, presumably via the 3' phosphate group. The location of sites of breakage with both duplex and single-stranded DNA is not random. In all these respects the wheat germ enzyme closely resembles the rat liver type 1 topoisomerase. A comparison of the locations of the sites of breakage in duplex DNA generated by the topoisomerases from wheat germ and rat liver indicates a number of common sites, although the patterns of breakage are not identical.
对小麦胚芽1型DNA拓扑异构酶在双链和单链DNA中造成链断裂的特性进行了研究。双链DNA中的链断裂取决于使用变性条件使酶失活并终止反应，而单链DNA的断裂则发生在正常反应条件下，且不依赖于变性。断裂产生一个游离的5'羟基，酶与断裂处的3'侧结合，推测是通过3'磷酸基团。双链和单链DNA断裂位点的位置并非随机。在所有这些方面，小麦胚芽酶与大鼠肝脏1型拓扑异构酶非常相似。对小麦胚芽和大鼠肝脏拓扑异构酶在双链DNA中产生的断裂位点位置进行比较，结果表明存在一些共同位点，尽管断裂模式并不相同。
