In E. coli, to repair a thymine dimer by nucleotide excision repair, in which order do the necessary enzymes act?
A) nuclease, DNA polymerase, RNA primase
B) helicase, DNA polymerase, DNA ligase
C) DNA ligase, nuclease, helicase
D) nuclease, DNA polymerase, DNA ligase

Question

Quizplus · Accepted Answer

Nucleotide excision repair involves the removal of a section of DNA containing the thymine dimer, followed by resynthesis of the DNA using the undamaged strand as a template. The enzymes involved in this process are a nuclease (to cut the DNA), DNA polymerase (to resynthesize the DNA), and DNA ligase (to seal the nick created by the nuclease). Therefore, the correct order of enzyme action would be nuclease, DNA polymerase, and DNA ligase. Choice D is the only option that follows this order.

In E Coli, to Repair a Thymine Dimer by Nucleotide Excision