title: Sensitivity of the quorum sensing system is achieved by low pass filtering.
abstract: Autoinducer sensing, also known as quorum sensing, is the communication of bacteria by autoinducer (small signaling molecules). Cells respond on extremely low concentrations of autoinducer: only one or two molecules per cell are sufficient. At this signal level a high degree of noise is inherent. We ask for the mechanism that is able to overcome the stochasticity of the signal. By means of a model and parameter fitting we show that the sensing module acts as a low pass filter, representing the biochemical equivalent of a moving average. It is shown that the system works most sensitive in the range of 0-50 nM autoinducer. Moreover, the time scale of the reaction depends on the signal strength in a crucial manner. Nonlinear feedback is able to further enhance the sensitivity. The biological implications of the low pass filter property are discussed.
authors.affiliation: Technical University Munich, Centre for Mathematical Sciences, Boltzmannstr. 3, D-85748 Garching, Munich, Germany.johannes.mueller@mytum.de
authors.forename: Johannes
authors.initials: J
authors.lastname: Müller
authors.forename: Christina
authors.initials: C
authors.lastname: Kuttler
authors.forename: Burkhard A
authors.initials: BA
authors.lastname: Hense
mesh_terms: D048908:Aliivibrio fischeri / Q000502:physiology; D008954:Models, Biological; D053038:Quorum Sensing