Figure 5.

QS influences biofilm formation and physiology

AIs are continuously being produced by bacteria; they constantly move in and out of the cell by diffusion, active transport, or into vesicles, depending on their chemical nature. When the concentration of AIs reaches a threshold level as consequence of increased cell density, the detection response is enabled, and they bound to the corresponding membrane-associated or intracellular receptors, activating these response regulator proteins. As a consequence, signal processing leads to collective transcription of target genes to produce a communal behavior of the bacterial population. One of the potential responses is the expression of a series of beneficial traits involved in biofilm physiology.