Periplasmic expression of biologically active vesicular stomatitis virus phosphoprotein P in Escherichia coli.

Overexpression of a clone of vesicular stomatitis virus phosphoprotein P (New Jersey serotype) using T7 promoter with phoA leader sequence and a simpler two-step purification procedure of the expressed protein has been developed. The purified protein retains its ability to activate the transcription reaction. Comparative transcriptional assay using the protein P purified from periplasmic space and from cytosol (in the form of inclusion body) of Escherichia coli establishes the fact that the former is 10 times more efficient than the latter in activating the transcription reaction in vitro.