Modelling production of extracellular polymeric substances in a Pseudomonas aeruginosa chemostat culture

Formation of extracellular polymeric substances (EPSs) by mucoid Pseudomonas aeruginosa was investigated using literature data from chemostat cultures. The data were used to calibrate a product formation regime allowing substrate sufficient and endogenous EPS formation. Yield coefficients for both formation conditions were elucidated based on metabolic pathway analysis. Growth and non-growth related specific formation rates of 0.18 g CEPS/g Ccell/h and 0.03 1/h were estimated, respectively. The exogenous and endogenous EPS yield was found to be 0.77 g CEPS/g Cglu and 0.79 g CEPS/g Ccell, respectively. Being structurally equivalent to comprehensive maintenance models, this model allows for non-growth related product formation, showing the same quality of fit as previous models restricted to exogenous EPS precursors.