Use of a Coulter Counter to Detect Discrete Changes in Cell Numbers and Volume During Growth of Escherichia coli

Escherichia coli could be detected at a concentration of 10 5 cells/ml. Growth curves of the organism grown in filtered tryptone soya broth were made by taking viable and Coulter counts. Both curves were similar in shape and varied little during 10 h growth. Cell volume and volume distribution were seen to vary considerably however, volume reaching a stable minimum value of 0·61 μm 3 after 8 h. The Coulter Counter was considered to be potentially useful for detecting significant bacteriuria.