The nanofabrication of microfluidic devices allows us to monitor biomolecular reactions far from equilibrium. In such experiments, short-lived high-energy states in reactions such as protein folding and protein interactions can be transiently populated. In addition, single-molecule live-cell imaging requires the imaging of a large number of cells under defined conditions, e.g. the growth conditions have to be changed according to the experimental requirements. For example, stochastic switching into the competence mode of B. subtilis is triggered by nutrient limitation. To realize these requirements in an integrated manner, we plan to grow the cells directly on the microscope in temperature controlled microfluidic bioreactors. These experimental platforms are especially crucial for studies of population heterogeneity and gene expression noise. For the production of these devices, suitable clean room facilities for the microfabrication are provided at the Weizmann campus.
Coupled folding and binding of two intrinsically disordered proteins mapped with single-molecule FRET in a microfluidic mixing device.