Cellular reproduction and extracellular polymer formation by pseudonomas aeruginosa in continuous culture

Abstract

The kinetics of cellular reproduction and the rate and extent of synthesis of extracellular polymeric substances (EPS) were investigated for P. aeruginosa growing in glucose-limited chemostats. μmax and Ks estimates of 0.4 h−1 and 2 mg glucose C/L, respectively, at 25°C were obtained for this bacterium. The extent of EPS formation was inversely related to the growth rate of P. aeruginosa. The rate of EPS formation had both growth- and non-growth-associated components. The growth-associated polymer formation rate coefficient (k) was 0.3 mg polymer C/mg cellular C and the non-growth-associated polymer formation rate coefficient (k′) was 0.04 mg polymer C/mg cellular C/h. The values for k and k′ must be regarded as provisional since the product formation data were quite variable at low dilution rates. Estimates of the cellular (Yx/s) and polymer (Yp/s) yield coefficients were 0.3 mg cellular C/mg glucose C and 0.6 mg polymer C/mg glucose C, respectively. Most of the non-growth-associated consumption of glucose detected was due to exopolymer formation.