scholarly journals Studies on the Apoproteins of the Major Lipoprotein of the Yolk of Hen's Eggs I. Isolation and Properties of the Low-molecular-weight Apoproteins

1975 ◽  
Vol 28 (2) ◽  
pp. 121 ◽  
Author(s):  
RW Burley
Keyword(s):  
Molecular Weight ◽  
Low Density Lipoprotein ◽  
Guanidine Hydrochloride ◽  
Gel Filtration ◽  
Density Lipoprotein ◽  
Egg Yolk ◽  
Soluble Form ◽  
Low Molecular Weight ◽  
High Lipid ◽  
Low Molecular Weight Proteins

In a continuing study of protein-lipid interactions in egg yolk, the total apoprotei.n mixture (i.e. the 'apovitellenins') from the high-lipid, low-density lipoprotein (density 0�97 gJml) of the yolk from hen's eggs has been isolated in a soluble form. By gel-filtration chromatography in 6M urea the mixture has been separated into several fractions from which three new low-molecular-weight proteins (I, la, and 11), making up about 30% of the total, have been isolated. The most plentiful of these (I) consists of stable aggregates with several identical subunits each of molecular weight about 10000. This protein is analogous to the principal protein from the corresponding lipoprotein of emu's egg yolk, i.e. emu's apovitellenin I. Hen's apovitellenin I has a slightly different amino acid composition from that of the emu; notably it contains a sulphydryl group. The hen's protein also forms more stable aggregates that are dissociated by detergent and by guanidine hydrochloride but are stable in urea.

scholarly journals Studies on the Apoproteins of the Major Lipoprotein of the Yolk of Hen's Eggs II. The Dimer-Tetramer Transition of Apovitellenin I

1976 ◽  
Vol 29 (4) ◽  
pp. 317 ◽  
Author(s):  
RW Burley ◽  
WA Davies
Keyword(s):  
Molecular Weight ◽  
Optical Rotation ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Molecular Weight ◽  
Low Density ◽  
High Lipid ◽  
Aqueous Urea ◽  
Weight Protein ◽  
Low Molecular Weight Protein

Further studies have been made of the physical properties of hen's apovitellenin I, the principal low-molecular-weight protein from the high-lipid low density lipoprotein of the yolk of hen's eggs. The methods used included chromatography, sedimentation, viscosity, optical rotation, and spin labelling; the solvents used were aqueous urea, and, for some experiments, aqueous formamide. It is concluded that at neutral pH the protein is present in these solvents as an aggregate of molecular weight 36000 corresponding to a tetramer. Below about pH 4�5 solutions of the tetramer increased greatly in viscosity; furthermore, a covalently bound spin label increased in mobility. These changes were reversible and were apparently the result of dissociation of the tetramer to a dimer. This dissociation did not involve a change in the proportion of a-helix. In contrast to the results of previous experiments, it now seems probable that the apovitellenin I dimer is stabilized by an interchain disulphide bond.

scholarly journals Lipid-protein globules of avian egg yolk. Isolation and properties of globules stable in concentrated sodium chloride solution

1977 ◽  
Vol 166 (3) ◽  
pp. 619-624 ◽  
Author(s):  
D V Vadehra ◽  
J M Bain ◽  
R W Burley
Keyword(s):  
Chloride Solution ◽  
Sodium Chloride Solution ◽  
Low Density Lipoprotein ◽  
Gel Filtration ◽  
Density Lipoprotein ◽  
Egg Yolk ◽  
Cholesteryl Esters ◽  
Yolk Globule ◽  
New Type ◽  
Globular Particle

A new type of globular particle, the ‘insoluble yolk globule’, was isolated from the egg yolk of three avian species (hen, duck, and emu) by centrifugation or gel-filtration chromatography. These globules are stable in NaCl and urea solutions at concentrations that dissolve or disrupt other constituents of yolk, The isolated globules are about 1% of the dry yolk of hen's and duck's eggs but about 8% emu's-egg yolk. Most of these globules are less than 2 micrometer in diameter. Electron micrographs of sections show a preponderance of globules in the range 0.125-0.25 micrometer, each with a thick shell surrounding a feature-less anterior. Globules with the same appearance were seen in sections of unfractionated yolk. Two kinds of larger particles were also observed: (i) particles with a distinct outer membrane and a vesiculated interior; (ii) featureless spheres, possibly of lipid. The insoluble yolk globules comprise protein (8-11% by dry wt.), phospholipid (31-35% total lipid), triacylglycerols (49-53%), cholesterol (8%) and cholesteryl esters (2-3%); the variations being among species. The phospholipid is accessible to phospholipase C. The isolated protein is heterogeneous and resembles the apoprotein from the yolk low-density lipoprotein.

scholarly journals Effects of Low Molecular Weight and Unfractionated Heparin on Lipoprotein Lipase and Lipid Profile in haemodialysis patients

2021 ◽  
Vol 3 (1) ◽  
pp. 56-59
Author(s):  
Ahmad Jan ◽  
Shah Jahan ◽  
Nighat Aziz ◽  
Sikandar Ali Khan ◽  
Asia Asia ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Lipid Profile ◽  
Lipoprotein Lipase ◽  
Low Density Lipoprotein ◽  
Age Distribution ◽  
Density Lipoprotein ◽  
P Value ◽  
Low Molecular Weight ◽  
Significant Difference ◽  
Study Population

Introduction: In haemodialysis patients, mortality from cardiovascular disease is much greater than in the general population. The current study aimed to evaluate the effects of two different types of heparin, low molecular weight heparins (LMWH) and high molecular weight heparin (HMWH), on lipid profile in patients undergoing haemodialysis.Material & Methods: A total of 60 patients on haemodialysis were selected from two main hospitals of Lahore, Pakistan and were divided into two major groups based on the type of heparin used. A 5 ml blood sample was taken from the dialysis machine to get the serum and was kept frozen at -20ºC for analysis of total cholesterol, triglycerides, high-density lipoprotein, and low-density lipoprotein. Comparison of lipoprotein lipase activity between groups were evaluated by using the student t-test. A P-value of ? 0.05 was considered statistically significant.Results: Gender wise distribution of study population (n=60) was 67% (n=40) males and 33% (n=20) females. The age distribution of individuals varied from 39-43 years. Moreover, use of HMWH was high in males (73%) as compared to female (27%) with an average age of 39 ± 12 years where duration of haemodialysis was 4.44 ± 2.83. A significant difference in LPL activity related to different times in all patients was observed. A clearer difference observed in case of LDL where LPL activity was markedly different in both groups. Our data showed that individuals using LMWH had less chances of dyslipidaemia as compared to those using HMWH.Conclusion: LMWH is a useful and safe anticoagulant during haemodialysis as compared to HMWH.

Use of Sodium Polyanetholesulfonate-CaCl 2 for Removal of Serum Nonspecific Inhibitors of Rubella Hemagglutination: Comparison with Other Polyanion-Divalent Cation Combinations

1977 ◽  
Vol 6 (4) ◽  
pp. 348-358
Author(s):  
Mary L. Ellins ◽  
James B. Campbell
Keyword(s):  
Molecular Weight ◽  
Divalent Cation ◽  
Dextran Sulfate ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Molecular Weight ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Serum Lipoproteins ◽  
Antibody Testing

By using trypsin-treated human type O cells as indicators, we compared the abilities of four polyanion-divalent cation combinations (heparin-MnCl 2 ; high-and low-molecular-weight dextran sulfate-CaCl 2 ; and sodium polyanetholesulfonate [SPS]-CaCl 2 ) for removal of serum non-immunoglobulin (lipoprotein) inhibitors of rubella hemagglutination. The combination of SPS-CaCl 2 was found to be the most effective, precipitating completely the pre-β and β-lipoproteins and reducing the α-lipoprotein levels by more than 50%. Hemagglutination patterns after this treatment were clear and stable, and, when normal sera were tested, hemagglutination-inhibition (HI) titers were comparable to those obtained after standard heparin-MnCl 2 treatment. High-molecular-weight dextran sulfate-CaCl 2 removed serum lipoproteins almost as effectively as SPS-CaCl 2 . However, problems of nonspecific agglutination and the heavy hemagglutination patterns resulting made this combination unacceptable for routine purposes. Neither low-molecular-weight dextran sulfate-CaCl 2 nor heparin-MnCl 2 removed the pre-β lipoproteins completely, and occasionally traces of β-lipoprotein also remained after treatment. The presence of pre-β lipoproteins in normal sera after treatment may be of no consequence in the HI test since we have found that the very-low-density lipoprotein fractions obtained by ultracentrifugal methods from normal sera (those corresponding to the pre-β fractions obtained by electrophoresis) had no HI activity. However, very-low-density lipoprotein fractions from all hyperlipemic sera tested had HI activity (titers ranging from 1:16 to 1:1,024) which, in the majority of cases, was not eliminated after heparin-MnCl 2 treatment. In every case, treatment with SPS-CaCl 2 removed this nonspecific activity completely. Since hyperlipemic sera may occasionally be encountered in routine rubella HI antibody testing, we recommend the use of SPS-CaCl 2 rather than heparin-MnCl 2 for pretreatment of sera.

ISOLATION AND COMPOSITION OF AVIAN EGG YOLK GRANULES AND THEIR CONSTITUENT α- AND β-LIPOVITELLINS

1961 ◽  
Vol 39 (8) ◽  
pp. 1295-1307 ◽  
Author(s):  
R. W. Burley ◽  
W. H. Cook
Keyword(s):  
Molecular Weight ◽  
Low Temperature ◽  
Phosphorus Content ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Egg Yolk ◽  
Low Density ◽  
High Molecular Weight Complex ◽  
Yolk Granules ◽  
Hen’S Egg

The yolk granules from hen's egg represent on a dry basis 23% of the yolk solids, and they contain about 90% of the protein phosphorus, 95% of the iron, and nearly 70% of the calcium in yolk. Ultracentrifugal and other analyses on solutions of the granules show that they are 70% α- and β-lipovitellin in an approximate ratio of 1:1.8, 16% phosvitin, and 12% low-density lipoprotein. The properties and composition of the two lipovitellins isolated from the granules are the same as those isolated from solutions of whole yolk. Further purification reduces the protein phosphorus in α-lipovitellin to 0.50% and in β-lipovitellin to 0.27%, and this confirms that α-vitellin has a higher phosphorus content. Experiments at low temperature suggest that phosvitin exists in the granules as a high molecular weight complex.

The Effect of Low Molecular Weight Dextran Infusions on Plasma Lipids and Lipoproteins

1970 ◽  
Vol 38 (2) ◽  
pp. 233-244 ◽  
Author(s):  
T. P. Whitehead ◽  
P. W. Dykes ◽  
J. Gloster ◽  
P. Harris
Keyword(s):  
Molecular Weight ◽  
Plasma Lipids ◽  
Low Density Lipoprotein ◽  
Plasma Concentrations ◽  
Extracellular Fluid ◽  
Density Lipoprotein ◽  
Low Molecular Weight ◽  
Low Density ◽  
Dextran 40 ◽  
Lipids And Lipoproteins

1. Infusions of Dextran 40 induced a pronounced fall in the plasma concentration of cholesterol, in the absence of marked changes in plasma volume. Similar falls occurred in the plasma concentrations of phospholipids, triglyceride and low density lipoprotein. It was further observed that the return to normal was slow, and at 15 days was still incomplete. 2. Lipoprotein turnover studies failed to demonstrate altered rates of catabolism or evidence for altered synthetic rates. They were better interpreted in terms of redistribution from the plasma to the rest of the extracellular fluid, although there was no indication as to its exact site.

scholarly journals The Influence of some Fractions of Egg Yolk on the Survival of Ram Spermatozoa at 5oC

1975 ◽  
Vol 28 (2) ◽  
pp. 145 ◽  
Author(s):  
PF Watson ◽  
ICA Martin
Keyword(s):  
Molecular Weight ◽  
Ion Exchange ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Egg Yolk ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Low Density ◽  
Chromatographic System ◽  
Whole Egg

Ram spermatozoa were stored at 5�C in diluents containing various fractions of egg yolk prepared by dialysis, ultrafiltration and ion-exchange chromatography. They survived storage best in the presence of components of egg yolk which were non-dialysable and were not filtered through membranes which retained substances of molecular weight greater than 100000. The substances isolated in peak B of the ion-exchange chromatogram of whole egg yolk described by Seideman et al. (1969) gave greater protection than those from other fractions from this chromatographic system. These data indicate that the low-density lipoprotein fraction of egg yolk is the most likely source of protection to ram spermatozoa against the effects of storage at 5�C.

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