Genetic Analysis of Flagellar-Mediated Surface Sensing by PA14.

Surface sensing is a key aspect of the early stage of biofilm formation. For , the type IV pili (TFP), the TFP alignment complex and PilY1 were shown to play a key role in c-di-GMP signaling upon surface contact. The role of the flagellar machinery in surface sensing is less well understood in .

How cells with diverse stator composition collectively swarm.

Swarming is a macroscopic phenomenon in which surface bacteria organize into a motile population. The flagellar motor that drives swarming in is powered by stators MotAB and MotCD. Deletion of the MotCD stator eliminates swarming, whereas deletion of the MotAB stator enhances swarming.

How individual cells with diverse stator distributions collectively form a heterogeneous macroscopic swarming population.

Unlabelled: Swarming is a macroscopic phenomenon in which surface bacteria organize into a motile population. The flagellar motor that drives swarming in is powered by stators MotAB and MotCD. Deletion of the MotCD stator eliminates swarming, whereas deletion of the MotAB stator enhances swarming.

Surface-Induced cAMP Signaling Requires Multiple Features of the Pseudomonas aeruginosa Type IV Pili.

Pseudomonas aeruginosa type IV pili (TFP) are important for twitching motility and biofilm formation. TFP have been implicated in surface sensing, a process whereby surface-engaged cells upregulate the synthesis of the second messenger cAMP to propagate a signaling cascade leading to biofilm initiation and repression of motility. Here, we showed that mutations in PilA impairing proteolytic processing of the prepilin into mature pilin as well as the disruption of essential TFP components, including the PilC platform protein and PilB assembly motor protein, fail to induce surface-dependent cAMP signaling.