Table 1.

Criteria used to fit the parameters of the model to experimental data and the results for each criterion when using the nominal values in Table 2

Criteria
Description	Source	Fitted results
Under aerobic conditions, inactive FNR predominates   (X2,off>10X3,off)	Ref. 12	X2,off=4.63 µM 2X3,off=0.16 µMa
Under anaerobic conditions, active FNR predominates   (X3,on>10X2,on)	Refs. 5 and 12	X2,on=0.15 µM 2X3,on=3.48 µMa
Total aerobic FNR concentration is 4.8 µM	Ref. 3	4.79 µMa
Total anaerobic FNR concentration is 3.65 µM	Ref. 3	3.63 µMa
Removal of autorepression results in a 2-fold increase in   total FNR under anaerobic conditions	Ref. 13	2-fold
Reproduce the aerobic pulse-chase data	Ref. 8	RMS of 4.43b
Reproduce the anaerobic pulse-chase data	Ref. 8	RMS of 7.96b
Aerobic doubling time should be 60 min   (β31,off/2=0.0115)	Ref. 8	60.1 min
Anaerobic doubling time should be 90 min   (β31,on/2=0.0077)	Ref. 8	93.8 min
Critical level of active FNR should fall between 0.2 and 0.4 µM   (0.2<X3c<0.4)	Ref. 13	X3c=0.389 µM
The critical level of active FNR must be greater than its aerobic   steady-state concentration   (X3c>X3,off)	This study	X3c=0.389 µM X3,off = 0.08 µM
Dimerization and disassociation of the FNR dimer, under aerobic   conditions, should be faster than transcription of the fnr mRNA   (${\alpha }_{22}{X}_3{X}_6>{\alpha }_1{X}_3^{g_{13}}$, α22X3X6>α1,max, ${\mathrm{\beta }}_{22}{X^2}_2{X}_5>{\alpha }_1{X}_3^{g_{13}}$, β22X22X5>α1,max)	This study	α22X3,offX6,off=25.4 min−1 µM β22X22,offX5=25.4 min−1 µM α1(X3,off)g13=0.28 min−1 µM
Dimerization and disassociation of the FNR dimer, under aerobic   conditions, should be faster than translation of the FNR protein   (α22X3X6>α21X1, β22X22X5>α21X1)		α1,max=0.135 min−1 µM α21X1,off=0.078 min−1 µM α21X1,on=0.053 min−1 µM
Aerobic ClpXP-dependent degradation must be faster than dilution of the active FNR dimmer   (β21X2X4>β31X3)	This study	β21,offX2,offX4=0.075 min−1 µM β31,offX3,off=0.001 min−1 µM
Aerobic values of β21 and β31 must be larger than their anaerobic values   (β21,off>β21,on, β31,off>β31,on)	This study	β21,off/β21,on=1.3 β31,off/β31,on=1.56

Here, X_i,off and X_i,on refer to the off (aerobic) and on (anaerobic) steady-state values of X_i.

^aExpressed in terms of the molecular weight of the FNR monomer.

^bRoot mean square.