This project has been directed towards the evaluation of the effect of electrical fields, AC and DC, on the metabolism and growth of microorganisms. Test systems used were batch culture, (Aerobic and anaerobic), continuous culture, and the use of genetic mutants for membrane transport studies. Voltages were applied to cell suspensions with inert platinum and carbon electrodes, and were limited to levels below the onset of electrolysis of water. Care was exercised in maintaining constant temperatures for comparative experiments, since one direct effect of applied currents was resistive heating of the solutions. The growth medium was designed so that the carbon source (usually glucose) was the limiting nutrient. For most of the studies, analysis of cell growth and glucose utilization was used to evaluate the effects of electric fields. (Modified author abstract)