DIFFERENTIAL EXPRESSION OF RECOMBINANT FUSION PROTEINS CONTAINING AMINO-XYTERMINAL AND CARBOXYTERMINAL REGIONS OF EXTERIOR MAJOR GLYCOPROTEIN (GP46) OF HUMAN T-CELL LEUKEMIA-VIRUS (HTLV-I) IN ESCHERICHIA-COLI

We obtained a collection of plasmid clones on the basis of the tryptop han-regulated vector, These plasmids are capable of expressing fusion proteins that contain bacterial anthranilate synthase (AS) and differe nt regions of the exterior major glycoprotein (gp46) of human T-cell l eukemia virus (HTLV-I). We found a high level of proteolytic degradati on of AS-gp46 fusion proteins, which is independent of the bacterial L a protease. The expression of clones containing the N-terminal gp46 re gion between the PvuIl and SalI sites of the env HTLV-I gene was signi ficantly more stable but less antigenic. On the contrary, the fusion p rotein that contained only 35 amino acid residues encoded by the TaqI- TaqI fragment of the gp46 C-terminal region was susceptible to proteol ytic degradation at late stages of induction in Escherichia coli cells , but revealed a good serologic reactivity. The clones obtained can be used for diagnostics and for preparing monoclonal and polyclonal anti bodies.