THERMOSENSITIVITY OF POLIOVIRUS.

Wallis, Craig (Baylor University College of Medicine, Houston, Tex.) and Joseph L. Melnick. Thermosensitivity of poliovirus. J. Bacteriol. 86:499-504. 1963.-Polioviruses are thermosensitive agents, although thermoresistant strains have been obtained and reported in the literature. Such resistant strains can be developed by exposure of the virus to cystine during multiple-cycle yields. Thermoresistant strains can be converted to the thermosensitive state by passing the virus in cells maintained in a cystine-free medium, or by reducing the virus with glutathione. The thermoresistant variants seem to result from the conditions under which virus is grown and harvested. Consequently, many such thermostable polioviruses actually represent phenotypic rather than genotypic variation.