Fast protein chromatofocusing of human very-low-density lipoproteins

Isolation and quantitation of apolipoproteins A-I and A-II from human high-density lipoproteins by fast-protein liquid chromatography

Apolipoproteins (Apo) A-I and A-II from human high-density lipoproteins (HDL) were isolated and quantified by fast-protein liquid chromatography using a Superose 12 column (gel filtration) followed by a Mono Q column (anion-exchanger). The separation times were 45 min and 15 min, respectively. Identities of both apolipoproteins were confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by double immunodiffusion. Peak areas after Mono Q chromatography increased linearly with concentration for samples from 0.5 to 10 mg of protein with a mean ratio of Apo A-I to Apo A-II of 3.46 +/- 0.71 in normolipoproteinemic subjects. This precise technique is an alternative for preparing and quantifying both HDL apolipoproteins.

Separation of apolipoprotein B subfractions by high performance gel permeation chromatography

Apolipoprotein B has previously been thought to be a homogeneous protein. Recently, it has been shown by SDS polyacrylamide gel electrophoresis that it consists of several species with different molecular weights. The present paper reports the separation of very low density lipoprotein (VLDL) and chylomicron derived apolipoprotein B by high performance gel permeation chromatography in SDS. Apolipoprotein B subfractions B-100, B-48 and B-26 could be identified with molecular weights of 650 000, 278 000, 175 000 and with typical amino acid compositions of apolipoprotein B.