Protein Domain : CD-NTase-associated protein 3 IPR011952

Type	Family
Description	This family represents a group of proteins found in several proteobacteria, which are part of the CBASS (cyclic oligonucleotide-based antiphage signaling system), providing immunity against bacteriophage. This system is ancestry related with the cGAS-STING innate immune pathway in animals. CBASS systems are composed of an oligonucleotide cyclase and an effector that is activated by the cyclic oligonucleotides, promoting cell death. The CD-NTase protein synthesizes cyclic nucleotides in response to infection, which serve as specific second messenger signals that activate a diverse range of effectors, leading to bacterial cell death and thus abortive phage infection [ , ].CD-NTase-associated protein 3 (CAP3) is part of type II CBASS, which is thought to be an isopeptidase of the JAB/JAMM family, usually found in eukaryotic deubiquitinase enzymes that remove ubiquitin from target proteins. This protein is necessary for the protection against some phage infection suggesting its ancillary function in CBASS system. It is not yet known which protein is the target for CAP3, as ubiquitin is not known to be present in E.coli or V. cholerae [ ].
Short Name	CAP3