repair enzyme

biochemistry

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Last updated

July 16, 2026

Quick Summary

Repair enzymes are crucial biochemical tools that maintain the integrity of DNA. These enzymes constantly scan DNA for damage that can occur during replication or from external factors. If damage is detected, repair enzymes activate specific pathways to correct the lesions, preventing mutations that could harm cell function or be passed to future generations.1

One significant repair mechanism is base excision repair. This process begins when a DNA glycosylase enzyme identifies and removes a damaged base. An AP endonuclease then nicks the DNA strand, and subsequent steps involve filling the gap with correct nucleotides and sealing the strand. Other repair mechanisms, like mismatch repair, also exist to correct errors and ensure genetic accuracy.21

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heredity
Repair of mutation
Special repair enzymes either cut the bond between the thymines or excise the bonded dimer and replace it with two single thymines. If both of these repair methods fail, a third method allows the DNA replication process to bypass the dimer; however, it is this bypass…
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Special repair enzymes either cut the bond between the thymines or excise the bonded dimer and replace it with two single thymines. If both of these repair methods fail, a third method allows the DNA replication process to bypass the dimer; however, it is this bypass…
Read More