Expression of a bovine leukaemia virus envelope fusion protein in E. coli.

An expression plasmid containing 1.224 bp of the bovine leukaemia virus (BLV) env gene was constructed. The polypeptides encoded by six recombinant plasmids were analysed by electrophoretic transfer blot analysis. Two new proteins of 150-160 kDa and 60 kDa, respectively, were found in whole cellular extracts using sera of naturally infected cattle and/or by use of mouse monoclonal antibodies against gp51.