– Envelope protein which probably plays a role in virus entry into the host cell. Is probably involved in the virus attachment to the host cell surface and associates with the entry/fusion complex (EFC). Needed for fusion and penetration of the virus core into host cell. Vaccinia virus (strain Western Reserve) L1 Protein (His) is expressed in yeast with N-6xHis tag. The predicted molecular weight is 21.3 kDa and the accession number is P07612.