Stability Analysis On The Tryptophan Regulation Network In Escherichia Coli

As one of the twenty amino acids, the tryptophan (Trp) is a necessary since it can not be synthesized by human and thus can only be obtained from diet. Consequently tryptophan operon of Escherichia coli (E.coli) plays an important role in biosynthesis, medicine, and bio-industry. Basically, its regulation consists of three negative feedback loops:repression, transcription attenuation, and feedback enzyme inhibition. These loops are believed to be crucial to understand the dynamic of the regulation network. So far, however, its stability (either stationary or oscillation) is still a matter of some controversy in different model studies. In this paper, we aim to give our contribution to this problem.In the first introduction section, we give some basic knowledge of the amino acid and the Trp operon in bacteria E.coli.In the second chapter, we introduce some detailed models describing the Trp regulation network.In the third chapter, we simplify the interactions in the gene regulation, and introduce a bool network in order to give qualitative analysis. Both qualitative and quantitative analyses suggest that the Trp genetic regulation system is stable.