If mutation destroys the function of the Cas9 gene then the bacteria will not be able to target a specific bacteriophage for destruction upon infection for the second time.
<h3>What is the Cas9 gene?</h3>
Cas9 is a 160 kilodalton protein that plays a vital role in the immunological defense of certain bacteria against DNA viruses and plasmids and is heavily utilized in genetic engineering applications.
Its main function is to cut DNA and thereby alter a cell's genome.
Although Cas9 is an endonuclease and is evolved as a mechanism of immunity against viruses, they are not considered restriction enzymes.
