EXPRESSION IN ESCHERICHIA-COLI AND IN-VITRO PROCESSING OF HIV-1 P24 FUSION PROTEIN

Recombinant HIV-1 p24/p25 gag proteins were obtained from Escherichia coli using a cleavable fusion strategy. The fusion protein contains 28 0 amino acid residues of staphylococcal Protein A and 317 amino acid r esidues of p24/p25 flanking with the recognition/cleavage sequences fo r HIV protease. Fusion protein expressed under the control of lambda p hage promoter PR was purified by IgG-Sepharose affinity chromatography . The p24/p25 part of the fusion protein was released by recombinant H IV protease in vitro. After a second IgG-Sepharose affinity chromatogr aphy, the purified p24/p25 proteins were obtained in milligram quantit ies. The HIV-1 p24/p25 protein displayed antigenicity similar to those of native counterparts confirmed by Western blot assays and the Abbot t antigen test.