Question

In nucleotide excision repair in E. coli, the function of the UvrA/UvrB complex is to

A. detect DNA damage.

B. make cuts on both sides of the damage.

C. remove the damaged piece of DNA.

D. replace the damaged DNA with undamaged DNA.

Answer 1

The function of the UvrA/UvrB complex in nucleotide excision repair in E. coli is to detect DNA damage, such as thymine dimers, indicating the need for repair.

Step-by-step explanation:

In the process of nucleotide excision repair in E. coli, the function of the UvrA/UvrB complex is to detect DNA damage. The UvrA/UvrB complex scans the DNA for distortions in the double helix structure, which are indicative of damages such as thymine dimers caused by UV exposure. Upon detecting the damage, UvrA dissociates, and UvrB helps in recruiting UvrC to make incisions on both sides of the damage. Following this, UvrC and UvrD work together to remove the damaged fragment, and DNA Pol I synthesizes the correct DNA, while DNA ligase seals the backbone, restoring the integrity of the DNA molecule.