SnapShot: Electrochemical Communication in Biofilms

Abstract

The role of electricity in biological systems was first appreciated through electrical stimulation experiments performed by Luigi Galvani in the 18 century. These pioneering experiments demonstrated that the behavior of living tissues is governed by the flow of electrochemical species-an insight that gave rise to the modern field of electrophysiology. Since then, electrophysiology has largely remained a bastion of neuroscience. However, exciting recent developments have demonstrated that even simple bacteria residing in communities use electrochemical communication to coordinate population-level behaviors. These recent works are defining the emerging field of bacterial biofilm electrophysiology. To view this SnapShot, open or download the PDF.

The Computational Boundary of a “Self”: Developmental Bioelectricity Drives Multicellularity and Scale-Free Cognition

“…Electric circuits are very convenient for processing information (a fact that has not escaped the attention of computer engineers and evolutionary mechanisms of neural systems), because they facilitate integration of information over spatial domains, and form feedback loops (such as voltage-gated ion channels) that readily implement memories and homeostats (Pietak and Levin, 2017;Cervera et al, 2018). This proposal, of ancient bioelectrical systems of coordination at the dawn of multicellularity, has now been confirmed by elegant studies of brain-like integration of spatial information by ion flows in the proto-bodies known as bacterial biofilms, which show how group-scale goals can emerge in simple physiological systems (e.g., nutrient sharing in the bacterial collective) (Prindle et al, 2015;Humphries et al, 2017;Lee et al, 2017). In more advanced cell types, this same scheme is implemented not by extracellular ionic waves but by intracellular electrical synapses known as gap junctions -highly regulatable valves that allow cells to selectively share bioelectric state with neighbors and implement activitydependent plasticity (memory) (Palacios-Prado and Bukauskas, 2009;Zeng et al, 2009;Mathews and Levin, 2017).…”

The Microbiologist’s Guide to Membrane Potential Dynamics

“…However, recent studies revealed that the bacterial membrane potential is dynamicit can act as a tool for information signaling and processing. It is now evident that membrane potential regulates a wide range of bacterial physiology and behaviors, for example, pH homeostasis [3,4], membrane transport [5], motility [6,7], antibiotic resistance [8], cell division [9], electrical communication [10,11], and environmental sensing [12][13][14]. Here, we review the physiological roles of bacterial membrane potential as a source of free energy and as a means of information signaling and processing (Figure 1).…”

Electrical-charge accumulation enables integrative quality control duringB. subtilissporulation

“…Our study presents a new perspective in the emerging research field of bacterial biofilm electrophysiology (1). We showed the frequency of premature germination depends on the mother cells’ ability to uptake cations from their environment.…”

“…The significances of electrophysiological dynamics in bacteria has been uncovered in the last few years (1). Cells within Bacillus subtilis biofilms can communicate with each other through electrical signaling mediated by the gating of potassium channels (2).…”