P. Soudant et Fle. Chu, Lipid class and fatty acid composition of the protozoan parasite of oysters, Perkinsus marinus cultivated in two different media, J EUKAR MIC, 48(3), 2001, pp. 309-319
The meront stage of the oyster protozoan parasite. Perkinsus marinus, culti
vated in two media with different fatty acid profiles was analyzed for its
fatty acid and lipid class composition. The composition of fatty acids in t
he prezoosporangium stage of the parasite as well as that of the host oyste
r were investigated. Although the lipid class composition of meronts was do
minated by phospholipids and triacylglycerol, there was no triaclgycerol de
tected in either culture medium. Despite the difference in fatty acid compo
sition of the two media, the fatty acid composition of meronts in each medi
um was dominated by 14:0, 16:0, 18:0, 18:1(n-9), 20:1(n-9), 18:2(n-6) and 2
0:4(n-6), a profile that differed from its host. The quantities of total li
pids and fatty acids in meronts increased as the number of meronts increase
d and far exceeded the initial amounts in the media and in the initial cell
inoculum. The meronts harvested 25 d post-inoculation. had about 3 to 6 ti
mes higher total lipids and 4 to 13 times higher fatty acids than the amoun
ts contained in the media. The fatty acid profiles of both prezoosporangia
and oysters resembled each other and consisted primarily of 16:0, 20:4(n-6.
20:5(n-3), 22:2 Delta7,15, and 22:6(n-3). These results indicate that duri
ng meront proliferation, the parasite synthesizes certain fatty acids and l
ipid classes. For development from meront to prezoosporangium, the parasite
may rely on its host for lipid resources.