Partial Purification of Kuchijirosho Causative Agent by Sodium lotalamate Density Gradient Centrifugation

Abstract

To purify the kuchijirosho causative agent derived from brains of kuchijirosho-affected tiger puffer Takifugu rubripes, the method of density gradient centrifugation using iodinated contrast medium, Angio-Conray (solium iotalamata solution), was used. The extracts of kuchijirosho-affected brains were loaded on 3-55% gradient of Angio-Conray, and centrifuged at 280, 000 ×g for 2 h. The lethal activity to grass puffer Takifugu niphobles was found in a fraction with a density around 1.096 g/cm³. The infectivity of the extracts of kuchijirosho-affected brains was lost by treatment with ether, UV-irradiation, β-propiolacton or proteinase K.