Question

Adenine methylase is an enzyme used during mismatch repair (MMR). It helps determine which strand needs to be repaired by discriminating between template and new DNA strand. If this enzyme is mutated, how would MMR be affected

Answer 1

Answer:

The correct answer would be - MMR would be hindered because both strands would be unmethylated and both would appear as new DNA strands and it would not be able to determine which strand has the error .

Explanation:

In gene expression or DNA replication, the enzyme responsible for the synthesis of DNA from nucleoside triphosphate causes errors sometimes such as mismatch base pair that result in a change in genetic makeup.

For MMR, the DNA template and the strand formed required easily to be differentiated. As the newly synthesized strand is unmethylated and the DNA template strand is methylated results in DNA remain hemimethylated for a very short period.

After MMR, DNA adenine methylase enzyme that transfers a methyl group to the adenine of the sequence 5'-GATC-3' daughter strand formed.

Mutated DAM or DNA adenine methylase will not be able to transfer methyl group which leaves both template and daughter strands unmethylated and mismatch repair would be hindered as it will not be able to identify.