Identification of the lipid synthesized following the expression of At1g78690p in E. coli. A, one-dimensional TLC of polar lipids from E. coli transformed by empty pET15b (control) or pET15b-At1g78690 plasmids. CL, cardiolipin. B, identification of NAPE by PLD hydrolysis assay. Lane 1, standard NAE; lane 2, standard NAPE; lane 3, lipid of interest incubated 1 h without PLD; lane 4, lipid of interest incubated 1 h with PLD. PA, phosphatidic acid; C, negative ion ESI tandem mass spectrum of N-stearic-1-oleic-2-palmitoleic-3-phosphatidylethanolamine (m/z 980.6). D, fragmentation pattern of NAPE, illustrated by N-stearic-1-oleic-2-palmitoleic-3-phosphatidylethanolamine. The m/z values refer to the expected m/z.