Specific Differences in the Nucleic Acids from A and B Strains of Influenza Virus

Abstract

IT has recently been found that influenza virus A, strain PR8, contains only ribonucleic acid, no appreciable amount of deoxyribonucleic acid being present. The amount associated with the virus is rather small, however, preparations of high infectivity (LD50/HA > 6.0) containing between 0.8 and 1.0 percent^1,2. Although preparations of low infectivity (LD50/HA ∼ 3.2–4.5) were found to have significantly lower ribonucleic acid contents², the possibility still remained that the nucleic acid was not an integral part of the virus particle. A further method of investigating this possibility was to determine the overall ratios of the nucleic acid bases from different strains of influenza virus to see whether any relationship existed between the values obtained and any biological property, for example, serology. The preliminary results of such an investigation are reported here.