Determination of Kinetic Constants for Nitrifying Bacteria in Mixed Culture, with the Aid of an Electronic Computer

SUMMARY: An electronic computer was used to integrate differential equations for bacterial growth, and thus to determine simultaneously growth-rate constants, saturation (‘Michaelis’) constants, and initial numbers of bacteria. In one case numerical methods were necessary to effect the integration and the work would have been prohibitively great if a computer had not been used. By this means curves have been fitted to experimental data on the course of nitrification in water from the Thames Estuary. Kinetic constants for Nitrosomonas and Nitrobacter at various temperatures were obtained, and the rate of death of these bacteria in the absence of their substrates was estimated.