Genomic landscape of antiviral defense systems in prokaryotes and phages

Prokaryotes and their viruses have co-evolved for billions of years, resulting in emergence of numerous antiviral defense systems. With the development of bioinformatic technologies and experimental studies, more and more novel defense systems have been discovered in the near decades. However, the origin and mechanism of these systems are still largely unknown. This study provides a systematic analysis of 132 defense systems within 212,599 prokaryotic genomes, which should be the largest analyzed data so far, revealing the diversity and distribution of these systems across different taxonomic units. Our findings also reveal that not only well-studied bacteria, but also archaea and virus encode diverse antiviral defense systems with specific features. In summary, this work classify 132 known defense systems, provides a comprehensive view of prokaryotic defense systems and insights into the evolution of immune responses.