The consequence to a bacterial cell of a mutation that inactivated the enzyme that methylates the A of the sequence GATC in newly made DNA would be
A)failure to carry out replication
B)failure to correct thymine dimers.
C)failure to distinguish old and new DNA during mismatch repair.
D)inactivation of certain metabolic genes.
E)decrease in the mutation rate

Question

Quizplus · Accepted Answer

Methylation of the A of the sequence GATC in newly made DNA is an important mechanism for distinguishing old and newly synthesized DNA during mismatch repair. If the enzyme that methylates this sequence is inactivated, then the cell would fail to distinguish old and new DNA during mismatch repair. This would result in errors in DNA replication and an increase in mutation rate. However, it would not affect replication itself, correct thymine dimers or inactivate metabolic genes.

The Consequence to a Bacterial Cell of a Mutation That