Kinetics of inclusion body formation studied in intact cells by FT-IR spectroscopy

The aggregation of a recombinant lipase as inclusion bodies (IBs) was studied directly within intact Escherichia coli cells by FT-IR microspectroscopy. Through this approach, it was possible to monitor in real time the different kinetics of IB formation at 37 and 27 °C, in excellent agreement with the results of the SDS–PAGE analysis. Furthermore, insights on the residual native-like structure of the expressed protein within IB – both isolated and inside cells – were obtained by the secondary structure analysis of the Amide I band in the IB FT-IR spectra.