Lipoprotein
DATA No : TLP1001
INFORMANT : Kazuo Kondo
NAME : low density lipoprotein
| COMMON NAME | : | b-lipoprotein |
| SYMBOL | : | LDL |
| FORMULA | : | MOL.WT (average) : |
Biological Activities
In normolipidemia, LDL transports 60 to 70 percent of the total plasma cholesterol. Many epidemiological studies have demonstrated that LDL cholesterol levels show a positive correlation with coronary heart disease (CHD).(
Ref. 1008/
1009/
1010/
1011/
1012)
| PHYSICAL AND CHEMICAL PROPERTIES |
| MELTING POINT | : | Definition
LDL is defined as the lipoprotein fraction with the density range of 1.019 to 1.063 g/ml.(Ref. 1001) |
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| BOILING POINT | : | |
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| REFRACTIVE INDEX | : | |
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| OPTICAL ROTATION | : | |
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| DENSITY | : | 1.019-1.063 g/ml |
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| SOLUBILITY | : | Physical properties
Particle weight 2.5 106 , Diameter(nm) 19-25
Relative weight Composition (%)
Protein 20-25 Phospholipid 20-25 Free cholesterol 6-10 Cholesteryl ester 35-45 Triglyceride6-12
Apolipoproteincontribution (%) apo B 90-95 apo C Trace apo E Trace(Ref. 1006) |
| UV SPECTRA | : | |
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| IR SPECTRA | : | |
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| NMR SPECTRA | : |
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| MASS SPECTRA | : |
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| OTHER SPECTRA | : |
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LDL in Agarose Gel Electrophoresis
In agarose gel electrophoresis LDL migrates at the same position as
b-globulins, thus LDL is designated
b-lipoprotein.
Fig.1 through 4: Electrophorograms above electrophoretic patterns of anodically migrating lipoprotein fractions.
Fig.1: Red 7B stained lipoproteins.
Fig.2: Formazan dye developed cholesterol fractions.
Fig.3: Formazan dye developed triglyceride fractions
Fig.4: Fig.2 and Fig.3 superimporsed. Demonstrate relative positions and enabling ratio assessment of all triglyceride and choresterol fractions, including Lp(a), Lipo X, slow
a, IDL, and
b-VLDL.
[
Chromatogram 1001]
Structure and Composition of LDL
LDL is a spherical particle and in normal individuals ranges 20.0 to 23.0 nm in diameter. The average molecular weight is 2.3
10
6. Compared with other lipoproteins, LDL particles are relatively homogeneous in size and composition, however, LDL particles can be separated into several subfractions of increasing density and decreasing size. LDL consists of protein (20-25%), phospolipid (20-25%), free cholesterol (6-10% ), cholesterol ester (35-45%) and triglyceride (6-12%). Apo B-100 is the sole constituent apolipoprotein on LDL. It is presumed that the cholesteryl esters and triglycerides form the hydrophobic core, which is surrounded by a surface coat of apolipoprotein B, free cholesterol and polar phospholipid components oriented toward the aqueous medium.
[
Table 2001] (
Ref. 1001/
1002/
1003/
1004/
1005/
1006/
1007/
1015/
1207)
Metabolism of LDL
LDL particles are mainly derived from the catabolism of VLDL. Lipoprotein lipase(LPL) hydrolyzes most of triglycerides of VLDL. Concequently, VLDL is converted into IDL. A portion of IDL particles are removed to the liver via LDL receptor. Moreover, triglycerides of the remainder of IDL particles are hydrolyzed by hepatic triglycerides lipase (HTGL) and IDL is converted into LDL. LDL is taken in cells via LDL receptor on peripheral tissues and supplies cholesterols to cells. LDL is cleared from plasma via LDL receptor, predominantly in the liver.(
Ref. 1001/
1007/
1013/
1014/
1015/
1207)
[1001]
| AUTHOR | : | Gotto,A.M. Jr., Pownall,H.J., and Havel,R.J. (1986) Introduction to the Plasma Lipoproteins, in Methods in Enzymology vol.128 (Segrest,J.P. and Albers,J.J., eds),pp3-41, Academic Press, London |
| TITLE | : | |
| JOURNAL | : | |
| VOL | : | PAGE : - () |
[1002]
| AUTHOR | : | Lee, D. M., and Alaupovic, P. |
| TITLE | : | Studies of the composition and structure of plasma lipoproteins. Isolation, composition, and immunochemical characterization of low density lipoprotein subfractions of human plasma PubMed ID:4987416 |
| JOURNAL | : | Biochemistry. |
| VOL | : | 9 PAGE : 2244-2252 (1970) |
[1003]
| AUTHOR | : | Alaupovic,P., Lee,D.M., and WcConathy, W.J. |
| TITLE | : | Studies on the composition and structure of plasma lipoproteins. Distribution oflipoprotein families in major density classes of normal human plasma lipoproteins. PubMed ID:4337564 |
| JOURNAL | : | Biochem.Biophys.Acta |
| VOL | : | 260 PAGE : 689 -707 (1972) |
[1004]
| AUTHOR | : | Deckelbaum, R. J., Shipley, G. G., and Small, D. M. |
| TITLE | : | Structure and interactions of lipids in human plasma low density lipoproteins PubMed ID:188825 |
| JOURNAL | : | J Biol Chem. |
| VOL | : | 252 PAGE : 744-754 (1977) |
[1005]
| AUTHOR | : | Shen, M. M., Krauss, R. M., Lindgren, F. T., and Forte, T. M. |
| TITLE | : | Heterogeneity of serum low density lipoproteins in normal human subjects PubMed ID:7240955 |
| JOURNAL | : | J Lipid Res. |
| VOL | : | 22 PAGE : 236-244 (1981) |
[1006]
| AUTHOR | : | Eisenberg,S. (1991) Plasma Lipoproteins : Structure, Composition, Classification, and Metabolism, in Primary Hyperlipoproteinemias (Steiner,G. and Shafrir,E., eds),pp23-41, McGraw-Hill, U.S.A |
| TITLE | : | |
| JOURNAL | : | |
| VOL | : | PAGE : - () |
[1007]
| AUTHOR | : | Grundy,S.M. (1992) Role of Low -density Lipoproteins in Development of Coronary Artery Atherosclerosis, in Plasma Lipoproteins and Coronary Artery Disease (Kreisberg ,R.A. and Segrest, J.P., eds), pp93-124, Blackwell Scientific Publications, Boston |
| TITLE | : | |
| JOURNAL | : | |
| VOL | : | PAGE : - () |
[1008]
| AUTHOR | : | Kannel, W. B., Castelli, W. P., and Gordon, T. |
| TITLE | : | Cholesterol in the prediction of atherosclerotic disease. New perspectives based on the Framingham study PubMed ID:217290 |
| JOURNAL | : | Ann Intern Med. |
| VOL | : | 90 PAGE : 85-91 (1979) |
[1009]
| AUTHOR | : | Wilson, P. W., Garrison, R. J., Castelli, W. P., Feinleib, M., McNamara, P. M., and Kannel, W. B. |
| TITLE | : | Prevalence of coronary heart disease in the Framingham Offspring Study: role of lipoprotein cholesterols PubMed ID:7416024 |
| JOURNAL | : | Am J Cardiol. |
| VOL | : | 46 PAGE : 649-654 (1980) |
[1010]
| AUTHOR | : | Kannel, W. B., Gordon, T., and Castelli, W. P. |
| TITLE | : | Role of lipids and lipoprotein fractions in atherogenesis: the Framingham study PubMed ID:7342099 |
| JOURNAL | : | Prog Lipid Res. |
| VOL | : | 20 PAGE : 339-348 (1981) |
[1011]
| AUTHOR | : | Assmann,G. (1982) Low-Density Lipoproteins and Atherogenesis, in Lipid Metabolism and Atherosclerosis (Assmann,G., eds), pp76-80,Schattauer, Germany |
| TITLE | : | |
| JOURNAL | : | |
| VOL | : | PAGE : - () |
[1012]
| AUTHOR | : | Castelli, W. P., Anderson, K., Wilson, P. W., and Levy, D. |
| TITLE | : | Lipids and risk of coronary heart disease. The Framingham Study PubMed ID:1342260 |
| JOURNAL | : | Ann Epidemiol. |
| VOL | : | 2 PAGE : 23-28 (1992) |
[1013]
| AUTHOR | : | Eisenberg,S., Bilheimer,D.W., Levy,R.I., and Lindgren,F.T. |
| TITLE | : | On the metabolic conversion of human plasma very low density lipoprotein to low density lipoprotein. PubMed ID:4359865 |
| JOURNAL | : | Biochem.Biophys.Acta |
| VOL | : | 326 PAGE : 361 -377 (1973) |
[1014]
| AUTHOR | : | Eisenberg ,S., and Levy,R.I. |
| TITLE | : | Lipoprotein metabolism. PubMed ID:174409 |
| JOURNAL | : | Adv. Lipid Res. |
| VOL | : | 13 PAGE : 1 -89 (1975) |
[1015]
| AUTHOR | : | Jacson,R.l., Morrisett,J.D., and Gotto,A.M.Jr. |
| TITLE | : | Lipoprotein structure and metabolism. |
| JOURNAL | : | Physiol.Rev. |
| VOL | : | 56 PAGE : 259 -316 (1976) |
[1207]
| AUTHOR | : | Assmann,G. (1982) Biochemistry of Lipoproteins, in Lipid Metabolism and Atherosclerosis (Assmann,G., eds), pp14-53,Schattauer, Germany |
| TITLE | : | |
| JOURNAL | : | |
| VOL | : | PAGE : - () |
Last updated June 19, 2007. Copyright © 1989-2007 Japanese Conference on the Biochemistry of Lipids (JCBL). All rights reserved.
