DNA topoisomerase

enzyme

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Last updated

July 16, 2026

Quick Summary

DNA topoisomerases are enzymes that manage the supercoiling of DNA. They work by breaking and rejoining one or both strands of the DNA molecule, which helps to reduce excessive twisting or supercoiling. This process is crucial during DNA replication, where topoisomerases unwind and separate DNA strands to allow for accurate copying of genetic information. These enzymes are also involved in DNA repair and recombination processes. Topoisomerase inhibitors are a class of anticancer drugs that work by preventing these enzymes from repairing or unwinding DNA, leading to DNA breaks and ultimately cell death.12345

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heredity
DNA replication
A class of enzymes called DNA topoisomerases removes helical twists by cutting a DNA strand and then resealing the cut. Enzymes called helicases then separate the two strands of the double helix, exposing two template surfaces for the alignment of free nucleotides. Beginning at the origin of replication, a complex…
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A class of enzymes called DNA topoisomerases removes helical twists by cutting a DNA strand and then resealing the cut. Enzymes called helicases then separate the two strands of the double helix, exposing two template surfaces for the alignment of free nucleotides. Beginning at the origin of replication, a complex…
Read More