Relative in Vivo Activity and Simulated Sunlight-uv Stability of Inclusion Bodies od a Wild-Type and an Engineered Polyhedral Envelope-Negative Isolate of the Nucleopolyhedrosis Virus of Autographa californica

Abstract

Virus stability and infectivity during stressful conditions was assessed to establish guidelines for future virus filtration experiments and to contribute to the body of knowledge on a widely used virus. A recombinant baculovirus of Autographa californica M nucleopolyhedrovirus (AcMNPV), vHSGFP, was incubated at 15–65 °C. A 2-log decrease in virus infectivity occurred after virus incubation above 45 °C. The activation energy of virus deactivation was circa 108 kJ/mol. Dynamic light scattering revealed an increase in apparent virus particle size from 150 ± 19 to 249 ± 13 nm at 55 °C. Protein and DNA concentrations in solution correlated well with virus aggregation as temperature was increased. Infectivity of vHSGFP stored for 5 months at 4 °C or exposed to shear stress from stirring (100 rpm, 1.02 × 10−5 psi) and pumping (50–250 ml/min, 1.45 × 10−5 to 7.25 × 10−5 psi) did not change with time. Unlike temperature variations, cold storage and shear stress appeared to have little impact on infectivity.