Bacterial DNA polymerase I and DNA polymerase III perform different functions during DNA replication.

If a strain of E. coli acquired a mutation that inactivated DNA polymerase III function, would the cell be able to replicate its DNA? Why or why not?

Key Concepts

DNA Replication

DNA replication is the biological process by which a cell duplicates its DNA before cell division. This process involves unwinding the double helix and synthesizing new strands complementary to the original strands. It is essential for genetic continuity, ensuring that each daughter cell receives an exact copy of the DNA.

Roles of DNA Polymerases

DNA polymerases are enzymes that synthesize DNA molecules from nucleotides, playing crucial roles in DNA replication. DNA polymerase III is the primary enzyme responsible for the bulk of DNA synthesis during replication, while DNA polymerase I is involved in removing RNA primers and filling in gaps with DNA. Each polymerase has distinct functions that are vital for accurate and efficient DNA replication.

Mutations and Their Effects

A mutation is a change in the DNA sequence that can affect gene function and protein production. Inactivating DNA polymerase III would impair the cell's ability to replicate its DNA efficiently, as this enzyme is essential for synthesizing the leading and lagging strands. Without functional DNA polymerase III, the cell would struggle to complete DNA replication, potentially leading to cell death.