Studies on protein and nucleic acid metabolism in virus-infected mammalian cells. 1. Encephalomyocarditis virus in Krebs II mouse-ascites-tumour cells

Abstract

Paper describes the standard methods that have been used for the propagation of Krebs II (mouse-ascites tumour) cells and for the growth of EMCV in these cells. No previous results have been reported on the effect of EMCV infection on the level of DNA, RNA and protein in the Krebs cells. Used radioactive tracers. 1) Conditons are described for the propagation of Krebs II ascites-tumor cells and for measurement of the effects of infection by EMCV; 2) The rate of penetration of orotic acid and of valine into Krebs cells was measured. 3) During the period of rapid virus synthesis there was a marked increase in the rate of ribonucleic acid turnover and a decrease in the size of the intracellular nucleotide pool. 4) In all experiments, the infected cells showed a small increase in the rate of protein turnover during the first 2 hr -- may be associated with the need for synthesis of new enzymes before virus reproduction can commence. 5) There was no change in the total DNA, RNA or protein in infected cells. 6) A method of hemagglutinin assay was developed which gave results within 30 minutes.