Two research groups led by Chinese and French scientists show how a plant uses a unique mechanism to turn a virulent bacterium into a non-virulent one.
They previously showed that Xanthomonas campestris, a causal agent of black rot on cabbage, inject a protein called AvrAC to assist infection. AvrAC does so by adding a nucleotide to a plant protein called BIK1, and thereby inhibits a host process mediated by BIK1.
In this study, the researchers showed that plants possessed a decoy protein called PBL2 that looks like BIK1 which could be similarly modified by AvrAC. Instead of making plants more susceptible to the bacterium, the modification on PBL2 allowed plants to detect the pathogen and trigger immune responses.
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