Petrovskaya_2018_Extremophiles_22_141

Cell surface display is a popular approach for the construction of whole-cell biocatalysts, live vaccines, and screening of combinatorial libraries. To develop a novel surface display system for the popular scaffold protein 10th human fibronectin type III domain ((10)Fn3) in Escherichia coli cells, we have used an alpha-helical linker and a C-terminal translocator domain from previously characterized autotransporter from Psychrobacter cryohalolentis K5(T). The level of (10)Fn3 passenger exposure at the cell surface provided by the hybrid autotransporter Fn877 and its C-terminal variants was low. To improve it, the fusion proteins containing (10)Fn3 and the native autotransporter passenger Est877 or the cold-active esterase EstPc in different orientations were constructed and expressed as passenger domains. Using the whole-cell ELISA and activity assays, we have demonstrated that N-terminal position of EstPc in the passenger significantly improves the efficiency of the surface display of (10)Fn3 in E. coli cells.