Evaluation of viral contamination in a baculovirus expression system

Abstract

Insect expression systems based on baculovirus are widely used for generating recombinant proteins. Here, the infectivity of baculoviruses under the physiological stresses of ‘freeze–thaw’ and sonication and the baculoviral contamination of recombinant proteins after protein purification were evaluated. Our findings suggest that Nonidet P-40 (NP-40) treatment of baculoviruses completely abolishes their infectivity and that recombinant proteins purified with affinity beads do not include infectious baculoviruses. We therefore suggest that baculovirus is completely inactivated by NP-40 treatment and that recombinant proteins are unlikely to be contaminated with infectious baculoviruses after their affinity purification.