Isolation and Structure of a Nuclear Polyhedrosis Virus from Polyhedra of the Silkworm, Bombyx mori

抄録

Rate-zonal centrifugation of virus particles released from the alkaline solution of inclusion bodies from the silkworm larva showed that the nuclear polyhedra contained at least three different forms of the virus particles. These forms of the virus were separated in sucrose density gradient centrifugation. The best result of separation was obtained when Trisbuffer was used as gradient buffer. The nuclear polyhedra in the silkworm larva contained 80% of single and 20% of bundle virus rods. All of the separated virus had a developmental membrane. Detail studies on the relative infectivity of both the single and the bundle virus rods showed that they were almost equally infectious in hemocoelic inoculation to the silkworm pupa. The naked virus rod, i.e., virus particle having only an intimate membrane did not occur significantly under the present condition of investigation.