Using your knowledge of DNA repair pathways, choose the pathway that would be used to repair the following types of DNA damage. Explain your reasoning.

heavily damaged bacterial DNA

Key Concepts

DNA Repair Mechanisms

DNA repair mechanisms are cellular processes that identify and correct damage to the DNA molecules that encode an organism's genome. These mechanisms are crucial for maintaining genetic stability and preventing mutations that could lead to diseases, including cancer. Different types of DNA damage, such as single-strand breaks, double-strand breaks, and base modifications, require specific repair pathways.

SOS Response in Bacteria

The SOS response is a global response to DNA damage in bacteria, particularly in Escherichia coli. When DNA is heavily damaged, the SOS response is activated, leading to the expression of several genes involved in DNA repair and mutagenesis. This pathway allows bacteria to tolerate and repair extensive DNA damage, often through error-prone repair mechanisms that can introduce mutations.

Homologous Recombination

Homologous recombination is a precise DNA repair mechanism that uses a homologous sequence as a template to repair double-strand breaks. This pathway is essential for maintaining genetic integrity, especially in organisms with complex genomes. In bacteria, homologous recombination can also play a role in repairing heavily damaged DNA by accurately restoring the original sequence, thus minimizing mutations.