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content/3.defense-systems/abi2.md

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 # Abi2
+
 ## Description
+
+The Abi2 system corresponds to a group of abortive infection system: [AbiD](/defense-systems/abid), AbiD1 and AbiF.
+
 The Abi2/AbiD1 system of lactococci is composed of a single protein Abi_2 :ref{doi=10.1016/j.mib.2005.06.006}. Expression of the protein is toxic to the bacteria and is therefore highly regulated. Expression of the protein is triggered by the orf1 of phage bIL66 which results in inhibition of the phage RuvC-like endonuclease activity and stops phage multiplication. 
 
+## Molecular mechanism
+
+For AbiD1 :ref{doi=10.1128/jb.177.13.3824-3829.1995} (AAA79209), the expression of the protein is toxic to the bacteria and is therefore highly regulated. Expression of the protein is triggered by the orf1 of phage bIL66 which results in inhibition of the phage RuvC-like endonuclease activity and stops phage multiplication.
+
 
 ## Example of genomic structure