Thermal inactivation of³²P-poliovirus at 37°C and 50°C in the presence of NaCl with high molarity

Summary

Poliovirus labeled with³²P was heated at 37° C and 50° C. At 50° C, inactivation of infectivity is accompanied by an alteration of density and a release of RNA. By heating in the presence of 2 M NaCl, infectivity and physical structure are stabilized, but prolonging the time of incubation infectivity is lost more rapidly than normal density. At 37° C infectivity is inactivated more rapidly than physical integrity is destroyed in the absence of NaCl. In the presence of NaCl physical integrity is stabilized but infectivity is more rapidly inactivated. There seems to be no difference in the action of NaCl per se at both temperatures. Stabilization of infectivity at 50° C and enhancement of inactivation at 37° C by NaCl seem to reflect rather two different mechanisms of thermal inactivation, one operating by physical destruction and another not being dependend on it.