transActivity of the Norovirus Camberwell Proteinase and Cleavage of the N-Terminal Protein Encoded by ORF1

Abstract
The virus-encoded proteinase of Camberwell virus, a genogroup 2 norovirus, was synthesized inEscherichia coli. The purified proteinase had correct N and C termini and showedtransactivity in cell-free assays.transactivity was also demonstrated in COS cells transfected with constructs encoding either the proteinase or a proteinase-polymerase fusion. The N-terminal protein of ORF1 was cleaved in COS cells, possibly at the site E194/S.