From: PROKARYO: an illustrative and interactive computational model of the lactose operon in the bacterium Escherichia coli
Lactose operon model parameter list
0.02 m i n −1
Bacterial growth rate.
2 m b p
Lac promoter concentration.
180 m i n −1
Maximal transcription initiation rate of the lac promoter.
18.8 m i n −1
Translation initiation rate of lacZ transcript.
6.0×104 m i n −1
Maximal lactose uptake rate per permease.
0.48 m i n −1
lacZ mRNA dilution/degradation rate.
0.03 m i n −1
Lac permease degradation/dilution rate.
0.02 m i n −1
Lactose degradation/dilution rate.
Cooperative promoter-CAP binding site interaction
Polymerase binding probability to the lac promoter.
3.6 ×104 m i n −1
Max. rate of lac-to-allolac and lac-to-gal metabolism
2.6 μ M
CAP complex binding affinity to DNA based on external glucose concentration.
CAP complex binding affinity to external glucose.
Affinity of active repressor for Operator O 2.
Affinity of active repressor for Operator O 3.
Stability of the O 1- O 2- O 3-repressor complex.
Repression affinity of lac operon promoter
2.92 ×106 m p b
Allolactose-repressor subunit dissociation rate.
680 μ M
Half-saturation constant for lactose uptake rate.
Permease activity as a function of inside glucose concentration
1.0 μ M
Permease activity as a function of outside glucose concentration.
7.0 ×105 m p b
Max. transcription initiation rate of lac promoter