CHARACTERIZATION OF MEVALONATE-LABELED LIPIDS ISOLATED FROM PARASITE PROTEINS IN SCHISTOSOMA-MANSONI

Adult paired schistosomes incubated for 3 days in radiolabeled mevalon ate can effectively label at least 2 major proteins with apparent size s of 25 and 43 kDa. The 25-kDa mevalonate-labeled proteins comigrated with proteins that could be labeled with GTP. The lipids attached to t hese proteins were removed and resolved by HPLC and found to comigrate with known samples of farnesol and geranylgeraniol. Homogenates of th e schistosome when incubated with labeled farnesol pyrophosphate effec tively labeled a protein(s) with an apparent molecular weight of 43 kD a while homogenates incubated in the presence of labeled geranylgerany l pyrophosphate-labeled schistosome proteins with an apparent molecula r weight of 25 kDa. Our results demonstrate that Schistosoma mansoni h as the ability to covalently attach farnesol and geranylgeranyl to low -molecular weight proteins.