Lipids in the storage organs of three mermithid nematodes and in the hemolymph of their hosts

Trophosomes of the mosquito parasitic mermithid Romanomermis culicivorax and two strains of the simuliid parasitic mermithid Mesomermis flumenalis (Neomesomermis flumenalis) contained in order of prevalence: triacylglycerols, phospholipids, sterols and sterol esters. Triacylglycerols in the trophosomes comprised a wide array of fatty acids, sterol esters a smaller variety. The degree of unsaturation of triacylglycerols and sterol esters was greater for M. flumenalis than R. culicivorax. The haemolymph of the 3 host species (Aedes aegypti (L.), Prosimulium mixtum Syme & Davis/S. fuscum Syme & Davis and Simulium venustum Say) contained an assortment of fatty acids, with a higher degree of unsaturation in the simuliids than in the culicid. The overall lipid concentration of the blood of A. aegypti was unaltered by parasitism, but the mermithid caused an increase in the myristic acid: palmitic acid ratio in the free fatty acid fraction of the host's haemolymph.ADDITIONAL ABSTRACT:Analysis of the trophosomes of Romanomermis culicivorax and Neomesomermis flumenalis showed the presence, in decreasing order of concentration, of triacylglycerols, phospholipids, sterols and sterol esters. The degree of unsaturation of triacylglycerols and sterol esters was larger in N. flumenalis than R. culicivorax. Parasitism of Aedes aegypti resulted in an increase in the myristic acid: palmitic acid ratio in the free fatty acid fraction of the mosquito haemolymph..RE: 36 ref.; RN: 544-63-8; 57-10-3; SC: ZA; HE; CA; BE; PE; PA; VE; 0J; 0T; 0H; 0NSource type: Electronic(1