OPTIMIZED BACTERIAL PRODUCTION OF NONGLYCOSYLATED HUMAN TRANSFERRIN AND ITS HALF-MOLECULES

Transferrin is a glycoprotein functioning in iron transport in higher eukaryotes, and consists of two highly homologous domains. To study th e function of the glycan residues attached exclusively to the C-termin al domain, we have constructed a plasmid allowing production of nongly cosylated human transferrin in Escherichia coli. By molecular biologic al and genetic techniques, production was stepped up to 60 mg/l. Simil ar plasmids were constructed for production of the two half-transferri ns. The recombinant proteins accumulate in inclusion-body-like aggrega tes, where they appear to bind iron without causing bacteriostasis. Pr oteins active in iron binding have been purified from these inclusion bodies.