Multiplicity and global parametric sensitivity of structured biological models

For a paradigmatic biologically structured model multiplicity and global parameter sensitivity of a chemostat are investigated. The modeling assumptions are bisubstrate growth limitation by carbon and nitrogen sources, presence of two essential intracellular compartments, active protein synthesis system (PSS) and inactive genetic compartment. Variance based global sensitivity of the kinetic parameters is evaluated by the Extended Fourier Amplitude Sensitivity Test (FAST). Computer simulations reveal that multiplicity can be induced by carbon source product synthesis inhibition. Results of the FAST analysis show dominant sensitivity on the maximum specific rate coefficients for assimilation of carbon and synthesis of PSS compartment.