The Method of Electrical Conductivity in Studies on Bacterial Metabolism

Abstract

Electrical conductivity is a valuable criterion in studying bacterial metabolism. In skim milk cultures of Pseudomonas fluorescens and in peptone cultures of Achromobacter lipidis (an ammonia forming lipolytic organism isolated from cream) specific conductivity was directly proportional to ammonia production and, in the former cultures, also to ammonia plus amino N. Ammonia and amino N formations are interdependent processes, the former rate being 43.7% of the latter. In skim milk cultures of Lactobacillus odontolyticus, specific conductivity was a linear function of decreasing pH up to the isoelectric point. Such proportionalities are valuable aids for interpreting mechanisms of metabolism.