A microbiologist isolated a mutant strain of E. coli that is extremely susceptible to bacteriophage infection, by a wide range of bacteriophages. Which of the following genes might she explore as a possible site of the mutation that results in this phenotype?
A) A gene that encodes a small nucleolar RNA
B) A gene that encodes a Cas protein
C) A gene that encodes a Piwi-interacting RNA
D) A gene that encodes either a miRNA or a siRNA
E) A gene that encodes an immune RNA

Question

Quizplus · Accepted Answer

The Cas protein is part of the CRISPR-Cas system, which provides bacteria with adaptive immunity against bacteriophages. A mutation in a gene encoding a Cas protein could impair this defense mechanism, making the bacteria more susceptible to phage infection.

A Microbiologist Isolated a Mutant Strain of E