Cellular electrophysiology XXII. Effects of imposed potentiostasis on microbial systems

Abstract

The effects of imposed potentiostasis on Escherichia coli systems have been investigated. It was found by application of appropriate potentials with a potentiostat, that suspensions of these microorganisms removed metabolisable substrate from their aquasphere more rapidly than from their untreated controls. Further studies also demonstrated that under these controlled-potential conditions, a shorter induction period was required for initiation of growth, and a greater number of organisms were obtained from the same quantity of substrate. One possible explanation for the results obtained, is that the aquaspheric potentials developed under normal conditions are too highly reducing to be compatible with the normal kinetic behaviour of the redox systems contained within the living cell. This in effect will result in a slowing of these electron transport processes with concurrent decrease in growth rate and yield. This condition is apparently counteracted by imposing suitable less negative potentials on the biosystem.