Biochemical and structural studies of eukaryotic membrane proteins (MPs) are hindered by the very low abundance of this type of proteins in their natural tissues. This problem can be overcome by heterologous overexpression of MPs in simple microbial organisms, such as the bacterium Escherichia coli. However, MP overexpression in bacteria typically results in very small amounts of membrane-integrated protein or in accumulation of the target MP in inclusion bodies. We have employed genetic strategies to engineer the E. coli cell machinery to be able to achieve high-level expression of eukaryotic MPs. We have constructed MP fusions with the green fluorescent protein (GFP) and used fluorescence-activated cell sorting (FACS) to screen libraries of E. coli cells carrying different genetic modifications and isolate mutants that exhibit large increases in cell fluorescence due to enhanced MP production. In this manner, we have identified E. coli variants with the ability to produce markedly enhanced amounts of membrane-embedded protein for a variety of different MPs. Using these engineered bacterial strains, we have produced sufficient amounts of high-quality MPs which are currently under structural investigations.