On Multiple Regulatory Mechanisms in the Tryptophan Operon System in Escherichia coli: In silico Study of Perturbation Dynamics

摘要: Living organisms often exist in uncertain environments where changes are the norm. Cellular systems therefore require resilient regulatory mechanisms for timely and stable adaptation. Among various regulation motifs, multiple feedback control emerges as a common theme. The tryptophan operon system Escherichia coli regulates production ofintracellular using an apparatus of three mechanisms: repression, attenuation enzyme inhibition; each provides essentially same function but operates distinctly different ways. Here we aim to understand roles loop by studying transient dynamics perturbations types; reveal underlying relationships between individual macroscopic behaviour. We develop S-systems approximation existing model characterise introducing two measurable quantities: maximum disturbance (MD) recovery time (RT). Our simulation results showed that combined all significantly increases stability, broadening range kinetic parameters Enzyme inhibition was shown directly level variables after perturbations. Attenuation, on other hand, found speed up whereas repression lengthens time. method developed this paper defined measurements can be applied cellular systems.