An improved purification procedure for preparing potyviruses and cytoplasmic inclusions from the same tissue.

Twelve different potyviruses and cytoplasmic inclusion proteins were purified from a range of plant species utilizing a single purification protocol. Highly purified preparations have been obtained with yields that reflect the relative concentrations in the starting material; virus yields of up to 15 mg per 100 g of tissue were obtained. In some cases aggregation resulted in losses of significant amounts of virus to the inclusion fraction; this varied among preparations of the same virus. Preparations obtained from cesium gradients were typically unaggregated and essentially free of host materials. Purified virus was suitable for the production of antisera with high specific titers and low titers against healthy plant antigens. Both purified virus and RNA prepared from the virus retained infectivity. Purified RNA was free of detectable host plant nucleic acids, as complementary DNA preparations synthesized using virion RNA as template were highly virus-specific.