{"title":"Characterization of lipovitellenin components, and their relation to low-density liproprotein structure","authors":"J. Augustyniak, W.G. Martin, W.H. Cook","doi":"10.1016/0926-6542(64)90030-7","DOIUrl":null,"url":null,"abstract":"<div><p>When aqueous solutions of the LDF of egg yolk and its fractions LDF<sub>1</sub> and LDF<sub>2</sub> were extracted with ethyl ether, all yielded five derived components having sedimentation rates of about 4 S, 7 S, 13 S, 15 S and 17 S. The first three of these were isolated and had molecular weights of 2.9·10<sup>5</sup>, 11·10<sup>5</sup> and 13·10<sup>5</sup>, and lipid contents of 50, 67 and 44%, respectively. These components were formed sequentially in the order 7 S → 4 S → 13 S and hence all contain the same proteins, although different combinations of polypeptide chains may be present. Apparently a reduction in lipid content below 50% causes an aggregation of 4-S particles to form 13 S and other rapidly sedimenting products. The sizes of the protein moieties, computed from the molecular weight and lipid content of the native fractions LDF<sub>1</sub> and LDF<sub>2</sub> and the derived products 7 S and 4 S, are in the order 8, 4, 2 and 1, respectively, with the smallest unit size estimated to be (1.7 ± 0.16) ·10<sup>5</sup>. Evidently the size of the protein moiety decreases stepwise as the lipid content decreases down to 4 S and this behavior, plus aggregation at low lipid contents, yields detectable and separable components in both the natural and derived from of these lipoproteins.</p></div>","PeriodicalId":100171,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Lipids and Related Subjects","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1964-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6542(64)90030-7","citationCount":"14","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochimica et Biophysica Acta (BBA) - Specialized Section on Lipids and Related Subjects","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0926654264900307","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 14
Abstract
When aqueous solutions of the LDF of egg yolk and its fractions LDF1 and LDF2 were extracted with ethyl ether, all yielded five derived components having sedimentation rates of about 4 S, 7 S, 13 S, 15 S and 17 S. The first three of these were isolated and had molecular weights of 2.9·105, 11·105 and 13·105, and lipid contents of 50, 67 and 44%, respectively. These components were formed sequentially in the order 7 S → 4 S → 13 S and hence all contain the same proteins, although different combinations of polypeptide chains may be present. Apparently a reduction in lipid content below 50% causes an aggregation of 4-S particles to form 13 S and other rapidly sedimenting products. The sizes of the protein moieties, computed from the molecular weight and lipid content of the native fractions LDF1 and LDF2 and the derived products 7 S and 4 S, are in the order 8, 4, 2 and 1, respectively, with the smallest unit size estimated to be (1.7 ± 0.16) ·105. Evidently the size of the protein moiety decreases stepwise as the lipid content decreases down to 4 S and this behavior, plus aggregation at low lipid contents, yields detectable and separable components in both the natural and derived from of these lipoproteins.