title: A purification method for apolipoprotein A-I and A-II.
abstract: Apolipoproteins A-I and A-II were isolated from precipitates obtained by cold ethanol fractionation of human plasma. The starting material used in this report was precipitate B of the Kistler and Nitschmann method which corresponds approximately to fraction III of the Cohn and Oncley procedure. Through the use of urea, chloroform, and ethanol in appropriate concentrations, apolipoproteins A-I and A-II were isolated by a simple extraction technique avoiding time-consuming ultracentrifugation. Starting from 10 g of centrifuged precipitate B, approximately 100 mg of apolipoprotein A-I and 10 mg of apolipoprotein A-II were obtained. When incubated with normal human or rabbit plasma, both apolipoproteins were readily incorporated into high-density lipoproteins. Apolipoprotein A-I obtained by the cold ethanol method activated lecithin-cholesterol acyltransferase to the same extent as apolipoprotein A-I prepared by the classical flotation method. Apolipoprotein A-II had no such properties by itself, but was capable of potentiating lecithin-cholesterol acyltransferase activity of apolipoprotein A-I.
authors.affiliation: Institute of Biochemistry, University of Lausanne, Epalinges, Switzerland.
authors.forename: M C
authors.initials: MC
authors.lastname: Peitsch
authors.forename: A
authors.initials: A
authors.lastname: Kress
authors.forename: P G
authors.initials: PG
authors.lastname: Lerch
authors.forename: J J
authors.initials: JJ
authors.lastname: Morgenthaler
authors.forename: H
authors.initials: H
authors.lastname: Isliker
authors.forename: H J
authors.initials: HJ
authors.lastname: Heiniger
mesh_terms: D016632:Apolipoprotein A-I; D016633:Apolipoprotein A-II; D001054:Apolipoproteins A / Q000302:isolation & purification*; D015153:Blotting, Western; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood*; D014461:Ultracentrifugation
chemical_list: D016632:Apolipoprotein A-I; D016633:Apolipoprotein A-II; D001054:Apolipoproteins A; D007862:Phosphatidylcholine-Sterol O-Acyltransferase