A microcalorimetric study of the growth of Klebsiella aerogenes in simple salts/glucose media

Abstract

Heat output-time records or 'thermograms' produced during the aerobic growth of Klebsiella aerogenes in simple salts/glucose media with growth limiting glucose concentrations of 2.0, 1.0 and 0.5 g dm-3 were obtained using a flow-microcalorimeter fitted with an aerobic cell. These traces are interpreted in terms of the recorded oxygen tension, pH, glucose concentration and bacterial population of the culture. Heat output is greatest during the phase of exponential growth, indicating that here the organisms are most energetically inefficient. During the stationary phase aerobic processes, which give rise to a low oxygen tension, produce a smaller heat output until secondary metabolic processes are complete.