Expression of the vesicular stomatitis virus nucleocapsid protein controlled by the lambda PR and PL promoters in Escherichia coli

Expression vectors were constructed in which a cDNA specifying the vesicular stomatitis virus nucleocapsid (VSV N) protein was inserted near the translational initiation region downstream from the thermoinducible P_R or P_L promoter of bacteriophage λ. Expression of the VSV N-protein was determined by a radioimmunoassay with monoclonal antibody prepared against the VSV N-protein. The expression of the VSV N-protein in Escherichia coli was low with either system. However, the deletion of a part of leader sequence from the translational initiation signal to the VSV N-gene resulted in at least 30-fold increase in production of the VSV N-protein. The VSV N-protein in E. coli was also analyzed by radioimmune blot after separation of proteins by gel electrophoresis. Degraded proteins reacted with the antibody were also observed in the cell extracts.