Our lab is interested in high resolution characterization of the microbial “pan immune system”. To defend against frequent phage infections, bacteria evolved dedicated defense systems, including restriction-modification, CRISPR-Cas, abortive infection, and a large diversity of additional defense systems. Analysis of bacterial and archaeal genomes have shown that defense systems are non-randomly distributed in microbial genomes, and are clustered to specific genomic locations that were termed “defense islands”. Our lab is engaged in utilizing the concept of defense islands to systematically discover new defense systems in microbial genomes, and then to and study their mechanisms of action. We are also interested in the biology of defense islands, and seek to understand their properties and the biological and evolutionary reasons for their formation.