Dynamic influence of feedback enzyme inhibition and transcription attenuation on the tryptophan operon response to nutritional shifts

A mathematical model of the tryptophan operon is developed. This model considers all of the system known regulatory mechanisms: repression, transcription attenuation, and feedback enzyme inhibition. Special attention is paid to the estimation of all the model parameters from reported experimental data. The model equations are numerically solved. An analysis of these solutions reveals that transcription attenuation helps to speed up the operon response to nutritional shifts, while enzyme inhibition increases the operon stability.