Reversible inhibition of poliovirus ribonucleic acid

Summary Monkey kidney tissue culture (MKTC) cell homogenate depressed the infectivity of poliovirus RNA. This depression, however, was not due to RNAase activity of the cell homogenate, since after the depressed RNA solution was diluted and fresh facilitator was added, the infectivity was restored. Yeastolate, egg white, casein hydrolysate, and commercial RNA and DNA were found to have the same inhibitory effect on infectious RNA. The inhibitors destroyed the facilitating capacity of the facilitator. They could be easily removed by adsorbing them to large quantities of facilitator. The 7 per cent phenol treatment and the 50 per cent phenol extraction of poliovirus to obtain infectious RNA were compared. If the resulting RNA solution was inoculated undiluted, the 50 per cent method was superior because this method removed the proteinaceous material and hence part of the inhibitors in the crude virus suspension.Aided by a grant from the National Foundation.