Virus-like particles in the ovary of an ichneumonid wasp: Purification and preliminary characterization.

Virus-like particles have been isolated from the oviducts of a parasitoid wasp, Hyposoter exiguae (Hymenoptera: Ichneumonidae). Particles are readily purified by centrifugation on either Ficoll or sucrose gradients. Double-stranded circular DNA isolated from purified particles is heterodisperse in terms of molecular weight; none of the molecules are sufficiently large to code for the aggregate of structural proteins comprising the particles. Preliminary Southern blot hybridization data suggest that there is minimal sequence homology between the different size classes of DNA examined.