Type II topoisomerases are topoisomerases that cut both strands of the DNA helix simultaneously in order to manage DNA tangles and supercoils. They use the hydrolysis of ATP, unlike Type I topoisomerase. In this process, these enzymes change the linking number of circular DNA by ±2.

拓扑异构酶（topoisomerase）是指通过切断 DNA 的一条或两条链中的 磷酸二酯键，然后重新缠绕和封口来更正DNA 连环数 的酶。 DNA拓扑异构酶 是存在于 细胞核 内的一类酶，他们能够催化DNA链的断裂和结合，从而控制DNA的拓扑状态，拓扑异构酶参与了超螺旋结构模板的调节。 哺乳动物中主要存在两种拓扑异构酶。 DNA拓扑异构酶I通过形成短暂的单链裂解-结合循环，催化 DNA复制 的拓扑异构状态的变化；相反，拓扑异构酶II通过引起瞬间 双链酶 桥的断裂，然后 …

2023年7月1日 · Numerous cancer chemotherapeutic drugs target Topo II enzymes. Selective targeting of Topo II for cancer treatment is an active field in research. Anthracyclines, epipodophyllotoxins and fluoroquinolones are Topo II inhibitors. The review summarizes their modes of action, and SARs from 2013 to 2023.

DNA topoisomerase II (topo II) are essential and ubiquitous enzymes that perform important intracellular roles in chromosome condensation and segregation, and in regulating DNA supercoiling.

Topo II catalytic inhibitors destroy cancer cells through the inhibitions of Topo II enzymatic activities, thus preventing the formation of Topo II–DNA complex without increasing DNA cleavage, via the mechanisms of action that include interfering with DNA binding, inhibiting cleavage of the DNA molecule, ATP hydrolysis, and binding to the ATP ...

2023年1月30日 · Etoposide, a chemotherapeutic poison of type IIA eukaryotic topoisomerases (topo IIs), promotes topo II to compact DNA by trapping DNA loops, creates DNA double-strand breaks, causes topo II to...

2009年4月20日 · Type II topoisomerases change DNA topology by generating transient DNA double strand breaks and are essential for all eukaryotic cells. Mammalian cells have two topoisomerase II (TOP2)...

拓扑异构酶I (type I topoisomerase, Top1) 催化产生DNA分子上的单链缺口,而拓扑异构酶II (type II topoisomerase, Top2) 则催化产生DNA 分子上的双链缺口。 Top2 在哺乳动物中又分为α 亚型和β亚型。 其中,Top2α 的功能主要与细胞的增殖和多潜能性相关,而Top2β 在神经发育中具有重要作 …

Type II topoisomerases are ubiquitous enzymes in all branches of life that can alter DNA superhelicity and unlink double-stranded DNA segments during processes such as replication and transcription. In cells, type II topoisomerases are particularly useful for their ability to disentangle newly-replicated sister chromosomes.

Type II DNA topoisomerase (topo II) is a type IIA topoisomerase that can relax both positively and negatively supercoiled DNA in an ATP- and Mg 2+-dependent manner. Topo II is required for the condensation, maintenance of structure, and segregation of daughter chromosomes following DNA replication, and it has also been linked to chromosome ...