Ref ID : 7369
Inui Hiroshi, Ohya Osamu, Isegawa Yuji, Kitaoka Shozaburo, Miyatake Kazutaka, and Nakano Yoshihisa; Effect of Cobalamin Deficiency on the Biosynthesis of Phosphatidylcholine in Euglena gracilis. J.Eukaryot.Microbiol. 43(3):177-180, 1996
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Euglena gracilis requires cobalamin (Cbl) as an essential growth factor. Phosphatidylcholine (PC) synthesis was greatly reduced by Cbl deficiency. Rapid cell division occurred after Cbl was replenished, and PC was actively synthesized during the cell divisions. When the deficient cells were given methionine (a precursor for the choline moiety), active synthesis of PC occurred even without the Cbl supplement, although cell division was not induced. As methionine synthase in Euglena requires methylcobalamin as a coenzyme, decrease in methionine synthesis may account for reduced PC synthesis under Cbl-deficient conditions. Phosphatidylethanolamine and phosphatidylserine synthesis were also suppressed, commensurate with decrease of PC synthesis under Cbl deficiency, even though Cbl is not thought to participate in their synthesis. In contrast, a lot of triglyceride and wax ester accumulated in Cbl-deficient cells. Moreover, Cbl depletion altered fatty acid composition, notably due to increased proportion of odd-numbered fatty acids.