Genetically engineered molecular networks for biosensing systems

Gene engineering has been successfully applied to develop biosensing materi al, which includes an enzyme-labeled binding protein for enzyme immunosensi ng, a lipid-tagged single chain antibody for immunosensing and an environme ntally responsive gene-bearing cell for environment sensing. protein A was labeled with firefly luciferase according to the gene engineering to fuse b oth proteins. A single chain antibody was genetically tagged with a lipid c hain at a specific site by enzymatic modification of a preprotein in a tran smembrane process within a bacterial cell. A recombinant plamid bearing xyl R protein and firefly luciferase genes with Ps promoter was transfected to E. coli to make the cell responsive to environmentally hazardous compounds such as xylene in emitting light. (C) 1998 Elsevier Science S.A. All right s reserved.