Studies on protein and nucleic acid metabolism in virus-infected mammalian cells. 5. The kinetics of synthesis of virus protein and of virus ribonucleic acid in Krebs II mouse-ascites-tumour cells infected with encephalomyocarditis virus

Abstract

The size and specific radioactivity of the nucleotide pool of Krebs II ascites cells was measured 30 minutes after addition of [6-14c]orotic acid to a suspension of cells in Earle''s medium. The effect of infection with encephalomyocarditis virus on both pool size and specific activity was also measured. The amino acid pool of normal Krebs cells was analysed. The effect of virus infection on the pool size and on the entry of [14c]valine into the pool was measured. The rate of synthesis of virus protein in Krebs cells was measured over 30 minute periods of the virus growth cycle. The relationship between time of synthesis of virus ribonucleic acid and virus protein was determined. Virus ribonucleic acid was found to be synthesized about 1 hour before virus protein. The formation of complete virus followed almost immediately after the synthesis of virus protein.