10 - 50 nM
||Weber M, Buceta J. Noise regulation by quorum sensing in low mRNA copy number systems. BMC Syst Biol. 2011 Jan 20 5 :11. doi: 10.1186/1752-0509-5-11. p.6 right column bottom paragraphPubMed ID21251314
|| Pai A, You L: Optimal tuning of bacterial sensing potential. Molecular systems biology 2009, 5(286) :286 doi: 10.1038/msb.2009.43.PubMed ID19584835
||p.6 right column bottom paragraph:"[Investigators] are interested in the role played by the fluctuations of the signaling molecule, A, when its concentration is close to the activation of the QS switch. Therefore, [they] fix the mean concentration of the autoinducer and modulate the rest of the parameters in order to keep constant this value. Pai and You [primary source] have recently studied the core architecture of the QS mechanism for a comprehensive set of systems. These authors have estimated that the critical concentration of autoinducer needed for the activation of the QS genes ranges from 10 to 50 nM for most of the bacterial species."