Apolipoprotein E is rich in

TYPES OF APOPROTEINS PRESENT IN VARIOUS LIPOPROTEIN FRACTIONS (CHEMISTRY OF APOPROTEINS)HDL: Two major apoproteins of HDL are designated as apo-A-I and apo-A-II. In addition to the above, HDL also contains apo-C-I, C-II, and C-III. HDL-3 is characterised by having apo-D and HDL may also acquire arginine-rich apo-E.LDL: The main apoprotein of LDL is apo-B100, which is also present in VLDL.Chylomicrons: Principal apoprotein of chylomicrons is apo-B48 (Mol.wt = 200 Kd). In addition, chylomicrons also contain apo-A (AI and AII) and apo-C (C-II and C-III), also arginine-rich apo-E (34 Kd). Apo- C seems to be freely transferable between chylomicrons and VLDL on one hand and HDL on the other.VLDL and LDL: Principal apoproteins of VLDL, IDL, and LDL is apo-B100 (350 Kd). They also contain apo-C (C-I, C-II, and C-III), and apo-E. IDL carries some apo-E apoprotein. Apo-E: Arginine-rich apo-E, isolated from VLDL. It contains arginine to the extent of 10 percent of the total amino acids and accounts for 5 to 10 percent of total VLDL apo-proteins in normal subjects but is present in excess in the "broad" b-VLDL of patients of type III hyperlipoproteinemia. Carbohydrate content: Carbohydrates account for approx. 5 percent Apo-B and include mannose, galactose, fucose, glucose, glucosamine and sialic acid. So, some of the lipoproteins are glycoproteins.Ref: Textbook of Medical Biochemistry 8th Edition Dr (Brig) MN Chatterjea, Rana Shinde page no: 445