Phospholipid fatty acid composition of hepatopancreatic brush-border membrane vesicles from the prawn Penaeus japonicus.

Brush-border membrane vesicles (BBMV) were isolated from prawn hepatopancreas as we previously described (Muriana et al (1993) J Biochem 113, 625-629). The characterization of hepatopancreatic BBMV (hBBMV) by monitoring the activity of marker enzymes indicated a relatively pure apical membrane preparation reduced in basolateral contamination. Phospholipid composition of hBBMV was examined by the Iatroscan TLC/FID technique, whereas the fatty acid profile of phospholipids was examined by capillary gas chromatography. Phosphatidylcholine and phosphatidylethanolamine are the principal phospholipids of these membranes. The major fatty acids of phospholipids are palmitic (16:0), palmitoleic (16:1n-7), stearic (18:0), oleic (18:1n-9), eicosapentaenoic (20:5n-3) and docosapentaenoic (22:5n-3) acids. Individual phospholipids are characterized by distinct fatty acid compositions, but display a similar ratio of unsaturated-to-saturated fatty acids and a similar unsaturation index.