Purification and characterization of epizootic diarrhea of infant mice virus

Epizootic diarrhea of infant mice virus has been purified from the intestines of infected mice using enzymatic digestion, precipitation with polyethylene glycol, extraction with Genesolv-D, and sucrose step-gradient centrifugation. The purified virus was found to be stable at -70 C or when treated with ether, chloroform, or sodium deoxycholate. Biochemical analysis of purified virions has suggested that the nucleic acid type of epizootic diarrhea of infant mice virus was of the ribonucleic acid type. Preparations of purified virions stained with phosphotungstic acid showed a particle with icosahedral symmetry, 54 +/- 2 nm in diameter and probably composed of 32 hollow capsomeres.