Abstract
Background : Insect specific DNA baculoviruses have been widely
used for biological control of insect pests to reduce cancers caused by
chemical application in agriculture and forestry and as vectors for high
yield exogenous protein expression. The most extensively studied and
widely used baculovirus is the Autographa californica multicapsid
nucleopolyhedrovirus (AcMNPV) due to its ability to replicate in many
permissive cells with high virus titer. During serial passage of AcMNPV
in permissive insect cells at high MOI, the fp25k mutates at a
high frequency leading to the development of the few polyhedra (FP)
phenotype with reduced polyhedra production and few virion occlusions in
polyhedra resulting in poor infectivity to insects.
Method and results: We used site-directed mutagenesis on wild
type AcMNPV (AcP3) fp25k gene to eliminate these hypermutable
sites and produced a recombinant virus AcP3-FPSDM and performed
restriction fragment length polymorphism (RFLP, as well as Western blot
analysis to understand virion occlusion efficacy. We comparedfp25k stability between AcP3 and AcP3-FPSDM in Hi5 cells. Our
experimental results showed that AcP3-FPSDM performed better in virion
occlusion efficiency.
Conclusion: We showed that AcP3-FPSDM is a better virus for
researchers to apply in agriculture and forestry to reduce chemical
usage, thus cancer cases.