Project 04

Regulation of potassium channel YugO in bacterial electrical

Principle Investigator: Inga Hänelt

Research Areas: Biochemistry, Microbiology, Structural Biology

Summary

Neurons have long been known to use electrical signaling for long-range communication. Recently, prokaryotes showed an important comparable function: in bacterial biofilms potassium ion channels mediate electrical signal transduction, which serves cell-cell communication allowing the communication within a biofilm, the synchronizationof two or more biofilms with each other and the attraction of motile bacteria to a biofilm. Interestingly, the electrical signaling even permits interspecies interaction, since potassium ions are essential currencies for all cells. Thus, electrical signaling might be much more universal than the well- described chemical signaling in biofilms via quorum sensing. The key player for electrical signaling in Bacillus subtilis is potassium ion channel YugO. Upon glutamate starvation within the interior cells of a biofilm, YugO supposedly opens leading to the efflux of potassium ions. The resulting hyperpolarization of the interior cells favors the uptake of glutamate while the more peripheral,depolarized cells consume less glutamate. Following a domino effect or chain reaction, the electrical signalpropagates through the biofilm enabling the diffusion of glutamate deep into the interior. This way, the survival of the whole bacterial community is assured. Biofilm formation is a characteristic of most multidrug-resistant bacteria. Disturbing the electrical signaling might thus be a new antibiotic strategy. However, to develop such a strategy molecular details are required. By microbial cell biology, structural biology, and biophysical approaches we will unravel the foundation of bacterial electrical signaling. Exemplarily for B. subtilis we will be able to answer how ion channel YugO gets activated on a molecular level, and which stimuli are responsible for the initiation of the signaling and for the propagation through the biofilm.