|Abstract or Summary
- A quantitative comparison was made of the incorporation of
14, C¹⁴ lipid compounds into Lee influenza virus. The compounds
tested were either lipids reported to be present in the virus or precursors
to virus lipid components. Infected chorioallantoic tissues
were incubated in medium containing the C¹⁴ metabolites. The
virus was purified by specific adsorption to chicken red blood cells,
ultracentrifugation and chromatography on an ECTEOLA anion exchange
column. The purified virus was titrated and the C¹⁴measured
by scintillation counting.
The C¹⁴ in the tissues was also determined. The incorporation
of the compounds into the infected tissues was measured and
compared to the uptake by normal tissues.
All but two of the compounds tested were incorporated into
the virus in significant amounts. Ethanolamine and choline,
precursors to phospholipids found in the virus, were not incorporated
into the virus. This suggested the major virus phospholipids were
synthesized before infection. However, glycerol, another phospholipid
precursor, was utilized in virus production. It is possible
that some of the minor phosphatides of the virus, such as phosphatidic
acid, were synthesized after infection.
It appeared that there was a significant decrease in fatty acid
synthesis after infection. Only a small amount of malonic acid was
incorporated into the virus. Due to their solubility, the fatty acids
supplied to the infected host cells were divided into two groups. The
long chain acids did not seem to be utilized to a great extent for
virus formation. The short chain acids contributed significantly
greater amounts of label to the virus, in terms of molar quantities,
than any of the long chain acids. The value for butyric acid was
greater than for any other fatty acid. In addition, this fatty acid
stimulated virus production nearly two fold.
The results suggested that most of the virus cholesterol was
preformed host material. There was little incorporation into the
virus and infected tissue from the precursor 3-hydroxy-3-methyl-glutaric acid-3-C¹⁴.
The infected tissue incorporated significant amounts of C¹⁴
from all of the compounds studied. There seemed to be a relation
between the amount of C¹⁴ incorporated into the tissue and that found in the virus, except in the case of ethanolamine and choline. Both
of these compounds were found in the infected tissues in substantial
amounts but were not utilized in new virus formation. Results
indicated that eight of the fourteen compounds tested were incorporated
significantly less in infected tissue than in control tissue.