Origin of phospholipid in bacteriophage PM2.

Phosphatidylethanolamine is the only phosphatide present in purified bacteriophage PM2 when obtained from bacteria grown and infected in minimal medium. The growth cycle of bacteriophage PM2 shows the basic general features described for virulent bacteriophages. PM2 infection of Pseudomonas BAL-31 causes a pronounced increase in deoxyribonucleic acid synthesis, but no detectable effect on the incorporation of phosphorus into lipid. When (32)P-prelabeled bacteria are infected with PM2, the specific activity of the phosphatide phosphorus in the virus is almost the same as that in the host bacteria labeled before infection. It is concluded that the viral phosphatide is not synthesized de novo after infection, but it probably is derived from preexisting cellular phosphatidylethanolamine.