Electrical Spiking in Escherichia coli Probed with a Fluorescent Voltage-Indicating Protein

Abstract

Introducing Bacterial Electrophysiology Bacterial electrophysiology has been limited by the inability to measure the membrane potential of single cells. Kralj et al. (p. 345 ) engineered a class of voltage-sensitive fluorescent membrane proteins to perform electrophysiological measurements on individual intact bacteria. These measurements showed that Escherichia coli generate electrical spikes, reminiscent of action potentials in neurons. The response of electrical spiking in bacteria was assessed in response to a wide range of physical and chemical perturbations, and was correlated with efflux activity. In the future, the probe should be useful in determining the roles of membrane potential in a variety of medically, environmentally, and industrially important bacteria.