The Effects of Amino Acids and Metals on the Infectivity of Poliovirus Ribonucleic Acid

Abstract

Most amino acids, except cysteine, protected the infectivity of phenol‐extracted poliovirus ribonucleic acid against inactivation during incubation at 37 C. Of these amino acids, histidine was most effective, whereas cysteine enhanced inactivation. Besides cysteine, three sulfhydryl compounds were also examined. Thioglycolic acid exhibited a similar effect as cysteine, but glutathione and mercaptoethanol were protective or enhancing in the inactivation of poliovirus RNA depending on the concentration of the drug. The effect of metal ions was diverse. Cu++ and Hg++ reduced the infectivity extensively, whereas Fe3+ and Al3+ were protective. Some of other metal ions were more or less inactivating, while the other metal ions examined were not. A protector and an inactivator of infectious RNA antagonized each other. © jointly owned by author and Igakushoin (Publisher)