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

Abstract

Formation of extracellular polymeric substances (EPS) by mucoid Pseudomonas aeruginosa is investigated using literature data from chemostat cultures. The data are used to calibrate a product formation regime allowing substrate sufficient and endogenous EPS formation. Yield coefficients for both formation conditions are elucidated based on metabolic pathway analysis, Growth and non-growth related specific formation rates of respectively 0.18 g CEPS/g Ccell/h and 0.03 1/h were estimated. 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.