Infective Ribonucleic Acid from the Viruses of Talfan and Teschen Diseases

Abstract

INFECTIVE ribonucleic acids have been obtained from several animal viruses by the cold phenol method described by Gierer and Schramm¹. In general, however, most of the experiments have been done with crude suspensions, and it has not always been clear whether the infective ribonucleic acid was derived from the virus itself or from a viral precursor or other related material. The work of Huppert and Sanders² with mouse encephalomyocarditis virus has shown clearly that the infective ribonucleic acid which can be obtained from mouse carcinoma cells infected with this virus has its origin in a viral precursor and not in the virus itself. In fact, infective ribonucleic acid cannot be extracted from this virus by the cold phenol method. On the other hand, it is likely that the infective material which can be obtained from suspensions of tissues infected with the viruses of poliomyelitis³, mouse encephalomyelitis⁴, Mengo encephalitis⁵, Murray Valley encephalitis⁶ and foot-and-mouth disease^7,8 by this method is being derived from the viruses themselves. This difference in behaviour emphasizes the differences in the chemical structures of the viruses. Furthermore, the work of Wecker⁹ has shown that purified Western equine encephalomyelitis virus, which does not yield any infective ribonucleic acid on treatment with cold phenol, can be made to do so if the extraction is carried out at 40–50° C.