Although
differences in the rate of virus fusion and budding from the host
cell membrane have been correlated with pathogenicity, no systematic
study of the contribution of differences in viral envelope composition
has previously been attempted. Using rigorous virus purification,
marked differences between virions and host were observed. Over 125
phospholipid species have been quantitated for three strains of influenza
(HKx31-H3N2, PR8-H1N1, and VN1203-H5N1) grown in eggs. The glycerophospholipid
composition of purified virions differs from that of the host or that
of typical mammalian cells. Phosphatidylcholine is the major component
in most mammalian cell membranes, whereas in purified virions phosphatidylethanolamine
dominates. Due to its effects on membrane curvature, it is likely
that the variations in its content are important to viral processing
during infection. This integrated method of virion isolation with
systematic analysis of glycerophospholipids provides a tool for the
assessment of species-specific biomarkers of viral pathogenicity