Question

During DNA replication, which enzyme can be disposed of in an organism with a mutant DNA polymerase that does not require a free 3 '- OH?

Short answer

Answer: Primase

Step-by-step solution

Understand the basic mechanism of DNA replication

DNA replication is the process by which a DNA molecule is copied to produce two identical DNA molecules. It involves the unzipping of the parent DNA double helix and the synthesizing of daughter strands using the parent strands as templates.

Identify the main enzymes involved in DNA replication

Some of the major enzymes involved in DNA replication include: 1. DNA helicase: unwinds the DNA double helix 2. DNA polymerase: adds nucleotides to the growing DNA chain 3. Primase: synthesizes short RNA primers 4. DNA ligase: seals nicks between newly synthesized DNA fragments

Understand the role of primase in DNA replication

Primase is responsible for synthesizing short RNA primers, which provide a free 3'-OH group to initiate DNA synthesis by DNA polymerase. DNA polymerases require a free 3'-OH group to add nucleotides to the growing DNA chain.

Understand the implications of a mutant DNA polymerase not requiring a free 3'-OH group

In an organism with a mutant DNA polymerase that does not require a free 3'-OH group, the enzyme can begin DNA synthesis without the need for an RNA primer. This implies that the primase, which synthesizes RNA primers providing the free 3'-OH groups for DNA polymerases, may no longer be necessary in this organism.

Determine which enzyme can be disposed of

Based on the analysis, the enzyme that can be disposed of in an organism with a mutant DNA polymerase that does not require a free 3'-OH group is the Primase. The mutant DNA polymerase can carry out DNA synthesis without the need for an RNA primer, making primase dispensable in this organism's DNA replication process.