Harnessing malE for the study of antigen/antibody recognitions

The construction of hybrids between the variable fragment (Fv) of antibodies and protein MalE of Escherichia coli at the genetic level makes possible their preparation in a functional state, independently of any interaction with the antigen. We used such hybrids and a mutagenesis approach to study the recognition between antibody D1.3 and its antigen lysozyme, and its maturation. We subsequently transformed D1.3 into a reagentless fluorescent biosensor by knowledge-based design.