title: Analytical study of the multiplicity of regulatory mechanisms in the tryptophan operon.
abstract: In this paper we study the stability of a previously introduced model for the tryptophan operon regulatory pathway. For this, we make use of the second Lyapunov's method. The results obtained for the wild-type and for a couple ofin-silico mutant bacterial strains allow a deeper understanding of the multiplicity of regulatory mechanisms in this operon. In particular, we confirm that enzyme inhibition and transcription attenuation strengthen the system stability, the effect of transcription attenuation being much shorter than that of enzyme inhibition. Furthermore, the analysis here presented provides some insights about how enzyme inhibition affects the system stability.
authors.affiliation: Depto. de Física, Esc. Sup. de Física y Matemáticas, Instituto Politécnico Nacional, Edif. 9, U.P. Zacatenco, 07738, México, D.F, México. moyo@esfm.ipn.mx
authors.forename: Moisés
authors.initials: M
authors.lastname: Santillán
authors.forename: Eduardo S
authors.initials: ES
authors.lastname: Zeron
mesh_terms: D000465:Algorithms; D000878:Anthranilate Synthase / Q000235:genetics / Q000378:metabolism; D001419:Bacteria / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D015536:Down-Regulation / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D008957:Models, Genetic; D009154:Mutation; D009875:Operator Regions, Genetic / Q000235:genetics; D009876:Operon / Q000235:genetics*; D012097:Repressor Proteins / Q000235:genetics; D014364:Tryptophan / Q000096:biosynthesis*; D029968:Escherichia coli Proteins
chemical_list: D000878:Anthranilate Synthase; D001426:Bacterial Proteins; D012097:Repressor Proteins; D014364:Tryptophan; C027190:TRPR protein, E coli; D029968:Escherichia coli Proteins