Definition of Topoisomerase Ii



Type II topoisomerases are such a type of topoisomerases that serve the purpose of cutting the strands of the double helix of DNA molecule at the same time. This helps in managing the tangles and supercoils present in the DNA molecule. This cutting is brought about by the action of ATP.

 


These enzymes tend to change the linking number of topoisomers by ±2. The topoisomerases II are further classified into IIA and IIB. They are essential for normal functioning and in relaxing the supercoils present in the DNA.

 


Example of Topoisomerase II:

The enzymes like DNA gyrase, eukaryotic topo II, bacterial topo IV, and topo VI all are topoisomerases II.

 

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