[A genetic method for exposing a given epitope at the surface of the bacterium Escherichia coli. Perspectives]

We describe a genetic method leading to insertion of a defined epitope into certain sites of a protein. This method is applied to LamB, an outer membrane protein from Escherichia coli K12. It allowed us to construct an "exposition vector". The bacterial clone harboring this vector with its passenger exposes the epitope at its surface. We discuss briefly some of the perspectives which are opened by this approach concerning the study of structure and localization of proteins, the development of live vaccines and the direct cloning and exposure of unknown epitopes.