Quorum-sensing signaling is required for production of the antibiotic pyrrolnitrin in a rhizospheric biocontrol strain of Serratia plymuthica.

One mechanism that bacteria have adopted to regulate the production of antimicrobial compounds is population-density-dependent LuxRI-type quorum sensing (QS), exploiting the production of N-acyl homoserine lactone (AHL) autoinducer signals. In biocontrol bacteria, most known cases involve the AHL control of phenazine antibiotics production by rhizospheric pseudomonads. This work is the first to demonstrate that phenazines are not the only group of biocontrol-related antibiotics whose production is regulated by QS systems.