Questions: Some anticancer and antiviral treatments include the use of nucleotide analogs (similar structure to the four found in DNA). These analogs, such as pentostatin (image below), compete with DNA nucleotides and incorporate into the DNA molecule and halting/preventing DNA replication from occurring. Which replisome enzyme is most likely affected? A) Ligase B) DNA Polymerase C) Helicase D) Topoisomerase

Some anticancer and antiviral treatments include the use of nucleotide analogs (similar structure to the four found in DNA). These analogs, such as pentostatin (image below), compete with DNA nucleotides and incorporate into the DNA molecule and halting/preventing DNA replication from occurring. Which replisome enzyme is most likely affected?
A) Ligase
B) DNA Polymerase
C) Helicase
D) Topoisomerase

Transcript text: TopHat: Some anticancer and antiviral treatments include the use of nucleotide analogs (similar structure to the four found in DNA). These analogs, such as pentostatin (image below), compete with DNA nucleotides and incorporate into the DNA molecule and haulting/preventing DNA replication from occurring. Which replisome enzyme is most likely affected? A) Ligase B) DNA Polymerase C) Helicase D) Topoisomerase

Solution

Solution Steps

Step 1: Understand the Problem

The problem describes the use of nucleotide analogs in anticancer and antiviral treatments. These analogs compete with DNA nucleotides and incorporate into the DNA molecule, preventing DNA replication. The question asks which replisome enzyme is most likely affected by this process.

Step 2: Identify the Role of Each Enzyme

Ligase: Joins Okazaki fragments on the lagging strand during DNA replication.
DNA Polymerase: Synthesizes new DNA strands by adding nucleotides to a pre-existing chain.
Helicase: Unwinds the DNA double helix ahead of the replication fork.
Topoisomerase: Relieves the tension created by the unwinding of DNA by helicase.

Step 3: Determine the Enzyme Affected by Nucleotide Analogs

Nucleotide analogs are incorporated into the DNA molecule, which would directly interfere with the synthesis of new DNA strands. This process is primarily carried out by DNA Polymerase.