Question

The 5'—>3' exonuclease activity of DNA polymerase I is unusual for what reason?

a. It works very slowly.
b. It works very quickly.
c. It degrades both RNA and DNA and exonucleases typically digest one or the other.
d. It is very general and has an extremely high KM.
e. It is very specific and has a very high KM.

Answer 1

The 5'—>3' exonuclease activity of DNA polymerase I is unusual because it degrades both RNA and DNA, while most exonucleases typically digest only one or the other. This activity allows DNA polymerase I to remove RNA primers during DNA replication and replace them with newly synthesized DNA. Additionally, the 5'—>3' exonuclease activity of DNA polymerase I is involved in DNA repair.

Step-by-step explanation:

The 5'—>3' exonuclease activity of DNA polymerase I is unusual because it degrades both RNA and DNA, while most exonucleases typically digest only one or the other. This activity allows DNA polymerase I to remove RNA primers during DNA replication and replace them with newly synthesized DNA. Additionally, the 5'—>3' exonuclease activity of DNA polymerase I is involved in DNA repair.