CRISPR’s Comrades in Arms Discovered in Microbial Genomes

CRISPR doesn’t stand against bacteriophages—viruses that infect bacteria—all by itself. No, this bacterial immune system has fellows deep in the microbial genome’s ranks. When these ranks were subjected to systematic inspection by researchers at the Weizmann School of Science, they were found to include 10 previously unknown immune defense systems. Some of these systems, like the CRISPR system, may be of use in genome editing.Besides CRISPR, bacteria have been known to re