Abstract
The kinetics of β-galactosidase induction in E. coli ML 3 have been studied. Following addition of inducer, the rate of enzyme synthesis accelerates from the uninduced to a steady-state rate. At saturating concentration of inducer the time constant (Tc) for this process is 2.5 to 3 minutes. With decreasing inducer concentration (I), increasing time constants are observed. I/I + K′ approximates I/Tc. The steady-state rate of β-galactosidase synthesis is approximated by I2/I2 + K2. K′ and K have been estimated for IPTG and TMG. The kinetics of β-galactosidase production after the removal of inducer by dilution or after the addition of glucose have been investigated. A transition time of 2.5 to 3 minutes is observed before enzyme synthesis slows or stops. These results are consistent with the hypothesis that the enzyme-forming unit is unstable.
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Selected References
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