Lipid and apolipoprotein composition of lipoproteins of European sea bass (Dicentrarchus labrax L)

Four lipoprotein fractions separated from Dicentrarchus labrax serum by density gradient and gel filtration chromatography show a direct relationship between molecular weight and lipid/protein ratio. Heavier molecules show a higher triglyceride content, whereas phospholipids are the main lipid class in the fraction with the lower molecular weight. A particularly complex apolipoprotein pattern is demonstrated in the isolated lipoproteins of D. labrax, characterised by an high number of apolipoproteins, varying from 19 in low-density lipoproteins (LDL) to 15 in high-density lipoproteins (HDL). Apolipoproteins with high molecular weight (from 263,000 to 216,000 Da), considered apo-B-like, are present in low-density lipoproteins, very-low-density lipoproteins and intermediate high-density lipoproteins. The most abundant apolipoproteins, present in HDL, are considered apo-AI-like (27,000 Da) and Apo-AII-like (12,000 Da).