FIGURE 4.
With the variation of parameter 
, a–c, plot in the 
versus 
plane of 
curve (thick line) and 
curve (thin line), the cross point of the two curves gives the steady state of the system. (d–f) The activity of 
and 
promoter change as a function of CI or Cro total concentration. The thick solid line represents 
, the thick shaded line represents 
, and the thin solid line represents 
. In these subfigures, the value of
is −6.3 kcal/mol in a and d; −3 kcal/mol in b and e, and −8 kcal/mol in c and f.