Conserved accessory proteins encoded with archaeal and bacterial Type III CRISPR-Cas gene cassettes that may specifically modulate, complement or extend interference activity

摘要: A study was undertaken to identify conserved proteins that are encoded either within, or directly adjacent to, cas gene cassettes of Type III CRISPR-Cas interference modules. These modules especially versatile functionally and have been shown target degrade dsDNA, ssDNA ssRNA. In addition, the frequently intertwined with other accessory genes, including genes encoding CARF domains, some which likely be cofunctional. Using a comparative genomics approach, defining association score accounting for coevolution specificity flanking we identified classified 39 new associated families. Most archaeal bacterial were seen flanked by several around half did not encode domains remain unknown function. Non-CARF found more diverse than their counterparts, nuclease, helicase, protease, ATPase, transporter transmembrane considerable fraction no known domains. The diversity non-CARF in this suggests additional families exist undetected because limited number annotated genomes currently available. method employed is scalable potential application on metagenomic data once automated pipelines annotation systems developed. All presented online readily accessible searchable format researchers audit model organism choice: http://accessory.crispr.dk .