Cloning and expression in Escherichia coli of the bovine papillomavirus L1 and L2 open reading frames

The two large open reading frames, LI and L2, in the nontransforming region of the bovine papilloma virus type 1 (BPV-1) genome were cloned and expressed in Escherichia coli . Each was constructed to be expressed in two forms: a naturally terminating protein fused to a non-BPV leader peptide and part of a larger fusion protein terminating with E. coli β-galactosidase (β-gal). Anti-BPV-1 sera identified a BPV-1-specific product for the naturally terminating LI, but not the L2, construction. Antisera generated against the β-gal fusions of both LI and L2 reacted with purified BPV-1, and this antisera neutralized purified virions, which prevented BPV-1 transformation of mouse C127 cells.