Topoisomerase inhibitors reverse the DNA damage brought on by transcription and replication. These enzymes are present in the cell nucleus. They control and help in the smooth functioning of the transcription and replication process. Along with this, they maintain the chromatin structure and play a vital role in cell survival.
Inhibition of topoisomerase causes cell death in bacterial and eukaryotic cells due to the formation of cross-links between the enzyme and the DNA of the bacteria. This halts the replication leading to cell death.