Toxin-antitoxin systems on the large defense plasmid pSYSA of synechocystis sp. pCC 6803

Abstract

Background: Cyanobacteria harbor a vast array of toxin-antitoxin modules, but their roles remain largely unknown. Results: The sll7003/ssl7004 system involves a VapC-type RNA endonuclease targeting single-stranded regions with little specificity. Conclusion: Seven different TA systems plus three free-standing components are located on plasmid pSYSA. Significance: Some bacterial plasmids are safeguarded against post-segregational loss by multipleTAsystems and an aggressive type of RNA-targeting toxicity. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.