title: Selective synthesis of the hexaenoic molecular species of ether-linked glycerophosphoethanolamine of Ehrlich ascites tumor cells.
abstract: In a previous study [Waku, K. and Nakazawa, Y. (1978) Eur. J. Biochem. 88, 489-494], we observed the rapid turnover rate of the molecular species of alkylacyl glycerophosphoethanolamine (Gro-P-Etn) containing docosahexaenoic acid and the high selectivity for this molecular species of ethanolamine phosphotransferase was suggested. To clarify this point, the incorporation of [14C]ethanolamine and [14C]CDP-ethanolamine into the individual molecular species of alkenylacyl, alkylacyl and diacyl Gro-P-Etn has been determined in Ehrlich ascites tumor cells. [14C]Ethanolamine was highly incorporated into the pentaenoic + hexaenoic species of alkenylacyl, alkylacyl and diacyl Gro-P-Etn, whereas incorporation of [14C]ethanolamine into molecular species other than the pentaenoic + hexaenoic species was quite low. The selectivity of ethanolamine phosphotransferase to form the molecular species of alkylacyl and diacyl Gro-P-Etn was examined by incubation of [14C]CDP-ethanolamine and microsomes of Ehrlich ascites tumor cells. The incorporation of [14C]CDP-ethanolamine was found to occur most into the pentaenoic + hexaenoic species of both alkylacyl and diacyl Gro-P-Etn. The present results suggest that the pentaenoic + hexaenoic species are preferentially synthesized among the various kinds of molecular species of alkylacyl and diacyl Gro-P-Etn by the ethanolamine phosphotransferase in Ehrlich ascites tumor cells.
mesh_terms: D000215:Acylation; D000478:Alkylation; D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000378:metabolism*; D019856:Ethanolamine; D004982:Ethanolaminephosphotransferase / Q000378:metabolism; D004983:Ethanolamines / Q000378:metabolism*; D008297:Male; D051379:Mice; D008861:Microsomes / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000096:biosynthesis*
chemical_list: D004983:Ethanolamines; D010714:Phosphatidylethanolamines; C002449:glycerophosphoethanolamine; D019856:Ethanolamine; D004982:Ethanolaminephosphotransferase