Bacteriophage T4 expression-packaging-processing vector that encapsidates HIV-type I GP120-V3 fusion protein inside...

Bacteriophage T4 as an expression-packaging-processing vector has recently been developed by using the T4 non-essential capsid scaffold protein IPIII(1-3). The IPIII gene was expressed at high level in E. coli from plasmid and was truncated at its C-terminus to permit construction of gene fusion in three different reading frames of EP-16 vector. Regulated higher-expression PPL reading frame vectors were also constructed. Infection of the plasmid-containing bacteria with bacteriophage mutants deleted for the IPIII gene showed that viable phage encapsidated and proteolytically processed the IPIII fusion proteins. An IPIII gene fused to human immunodeficiency virus type I (HIV-1) gp120 loop3 domain (V3) IPIII-V3 fusion gene products has been constructed and was packaged and processed within viable phage particle. The packaged fusion protein Gp120-V3 may be used for production of vaccine in the future.