lac operon induction in Escherichia coli: Systematic comparison of IPTG and TMG induction and influence of the transacetylase LacA

► IPTG and TMG are substrates of lactose permease at low concentrations. ► At high concentrations IPTG and TMG can enter the cells independently of lactose permease. ► Bimodal induction with IPTG occurs but is influenced by cell density. ► Transacetylase is responsible for IPTG depletion and hence influences induction.