Purification and characterization of a new reovirus from the Chinese mitten crab, Eriocheir sinensis

Abstract A new reovirus was recently isolated from a freshwater crab, the Chinese mitten crab, Eriocheir sinensis , in China. The complete viral particles are 55 nm in diameter, icosahedral, non‐enveloped and have a mean buoyant density of 1.39 g cm −3 in CsCl gradient. The viral genome is composed of 12 pieces of dsRNA with an electrophoretic pattern of 3/4/2/3. This virus infects connective tissue of the gills, gut and hepatopancreas. Partial cDNA cloning and sequence analysis showed that the RNA‐dependent RNA polymerase is located in the first RNA segment. From its biochemical, ultrastructural and physicochemical properties, this virus is quite different from the genus Aquareovirus (Reoviridae). It may represent a new genus of Reoviridae, different from the other crab reoviruses, P and W 2 .