Figure 2

Basic plasmalogen structure. (A) Plasmalogens are glycerophospholipids characterized by the presence of a vinyl-ether linkage at the sn-1 position and an ester-linkage at the sn-2 position. R1 and R2 represent straight-chain carbon groups. At the sn-1 position, the chemical moiety highlighted in red is an alkenyl group, which we use to measure plasmalogen abundance and molecular composition. These alkenyl groups are most commonly derived from C16:0, C18:0, or C18:1 fatty alcohols. The sn-2 position of plasmalogens is occupied typically by polyunsaturated fatty acids. X represents the head group, typically ethanolamine or choline for plasmalogens. In contrast, (B) diacylglycerophospholipids have ester-linkages at their sn-1 and sn-2 positions. As above, R1 and R2 represent straight-chain carbon groups and X represents the head group. Adapted from reference [31].