Review Article

Bacteriophages and Their Derivatives as Biotherapeutic Agents in Disease Prevention and Treatment

Figure 5

Overview of clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated (Cas) adaptive immunity. (a) Adaptation. The CRISPR arrays are composed of short repeats and intervening sequences derived from foreign invaders. Upon infection with a foreign element (e.g., phages), part of the genome is typically incorporated into the leader end of the CRISPR array and the repeat is duplicated. The CRISPR arrays are located adjacent to a cluster of Cas genes. (b) crRNA generation. The CRISPRs are transcribed into pre-crRNAs that are then processed into mature crRNAs. (c) Interference. The crRNA, in a complex with Cas proteins, binds and degrades the target nucleic acid of the invading element.
382539.fig.005