trp operon can run even in the presence of repressor. The attenuation system permits another 10-fold control over the operon’s activity. Thus, the combination of repression and attenuation controls the operon over a 700-fold range, from fully inactive to fully active: (70-fold [repression] X 10-fold [attenuation] = 700-fold).
#Unit 2. Cellular Organization#CELL CYCLE#Part B Pointers