Question

5 DNA pols in E. coli

pol I: (encoded by polA gene)
a) Major ____ enzyme for damaged DNA
b) Plays ____ role in semiconservative replication.
c) Most ___ (400/cell)
d) Molecular mass of 103 kD

Answer 1

DNA polymerase I in E. coli performs multiple functions in DNA replication, including repairing damaged DNA and synthesizing the lagging strand in semiconservative replication.

Step-by-step explanation:

In E. coli, the DNA polymerase I encoded by the polA gene plays multiple roles in DNA replication. It is the major enzyme involved in repairing damaged DNA, such as removing RNA primers and filling the gaps with DNA. It also plays a crucial role in semiconservative replication, where it synthesizes the lagging strand by adding nucleotides one by one to the growing DNA chain. In E. coli, there are around 400 molecules of DNA polymerase I per cell, and the molecular mass of the enzyme is approximately 103 kD.