The interaction of bovine milk caseins with the detergent sodium dodecyl sulphate. I. The relationship between the composition and the size of the protein–detergent aggregate

1970 ◽  
Vol 37 (2) ◽  
pp. 245-257 ◽  
Author(s):  
G. C. Cheeseman ◽  
Joan Jeffcoat
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Sodium Dodecyl ◽  
Bovine Milk ◽  
Maximum Amount ◽  
Protein Molecules ◽  
The Individual ◽  
The Relationship ◽  
Complete Dissociation

SummaryStudy of the dissociation of high-molecular-weight aggregates of preparations of αs1-, β-, κ-, and para-κ-casein by the detergent, sodium dodecyl sulphate (SDS), showed that there are differences in the aggregation properties of the individual caseins. Binding of detergent led first to the dissociation of casein aggregates and then to further interaction with the casein molecules. The amounts of detergent required to give the minimum sized protein-detergent aggregate when expressed as mg/mg casein were similar for κ-, para-κ- and αs1-casein but much less for β-casein. However, expressed as mole/mole the requirement for κ- and αs1-casein was similar but was twice that found for para-κ- and β-casein. The maximum amount of SDS bound was about twice that required for complete dissociation of the aggregates for κ-, para-κ- and αs1-casein but was 13 times greater for β-casein.Complete dissociation of κ-casein aggregates by SDS alone was not possible due to the presence of aggregates formed by disulphide linkages. These aggregates, which consisted of 3±1 protein molecules, accounted for about one-third of the κ-casein in the preparations examined.

A preliminary study by gel filtration and ultracentrifugation of the interaction of bovine milk caseins with detergents

1968 ◽  
Vol 35 (3) ◽  
pp. 439-446 ◽  
Author(s):  
G. C. Cheeseman
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Sodium Dodecyl ◽  
Bovine Milk ◽  
Gel Filtration ◽  
Sedimentation Velocity ◽  
Disulphide Bonds ◽  
Reducing Conditions ◽  
Preliminary Study ◽  
The Individual

SummaryThe detergents sodium dodecyl sulphate and octyl phenoxy polyethoxyethanol interact with casein and cause dissociation of the high-molecular-weight casein aggregates. It is presumed that the detergent binds with hydrophobic regions in the casein molecule. The size of the complexes formed between detergents and αs1-casein, β-casein and κ-casein, as estimated by gel filtration and sedimentation velocity experiments, suggests that the caseins were complexed as monomers.During gel filtration under non-reducing conditions, detergent-κ-casein complexes were separated from other major components because of their conversion through formation of disulphide bonds into high-molecular-weight aggregates. This reaction, which did not occur in sedimentation velocity experiments, was presumably facilitated by the changes in the equilibrium between the individual caseins during gel filtration.Sedimentation velocity experiments showed that a ratio of about 40 detergent molecules to 1 casein molecule was required to give the smallest casein-detergent complex.

scholarly journals Mapping of the genes controlling high-molecular-weight glutelin subunits of rye on the long arm of chromosome 1R

1984 ◽  
Vol 44 (2) ◽  
pp. 117-123 ◽  
Author(s):  
N. K. Singh ◽  
K. W. Shepherd
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Translocation Line ◽  
Sds Page ◽  
Chromosome 1R

SUMMARYThe gene(s) controlling the high-molecular-weight glutelin subunits in rye (designated as Glu-Rl) was mapped with respect to the centromere using a 1RL-1DS wheat-rye translocation line and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Analysis of 479 seeds from test-crosses between a 1R/1RL-1DS heterozygote and the cultivar India 115, revealed 14·6% aneuploid and 3·95% recombinant progeny. Excluding the aneuploids, this locus was calculated to be 4·65 ± 1·04 cM from the centromere on the long arm of chromosome 1R, which is comparable to the position of the homoeologous loci in wheat and barley.

scholarly journals Arterial basement-membrane-like material isolated and characterized from rabbit aortic myomedial cells in culture

1983 ◽  
Vol 211 (2) ◽  
pp. 397-404 ◽  
Author(s):  
L Heickendorff ◽  
T Ledet
Keyword(s):  
Molecular Weight ◽  
Basement Membrane ◽  
High Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Gel Electrophoresis ◽  
Periodic Acid ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Polyacrylamide Gel ◽  
Type I

Arterial basement-membrane-like material was isolated from rabbit aortic myomedial cell cultures by sonication and differential centrifugation. Isolated basement-membrane-like material was shown to be free of both cellular and matrix contaminants, on the basis of determinations of DNA, RNA, cholesterol, phosphorus and (Na+ + K+)-activated ATPase, combined with electron microscopy. Amino acid analyses showed that arterial basement-membrane-like material was composed of predominantly non-collagenous amino acids. Evaluated by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, reduced basement-membrane-like material comprised six major and about 30 minor components in the Mr range 10 000-600 000. One of the major peptides (Mr 225 000) was disulphide-linked. Periodic acid-Schiff staining of gels indicated that most high-molecular-weight components were glycoproteins. Two-dimensional gel electrophoresis resolved reduced basement-membrane-like material into more than 100 components, with pI from 5 to 7. The disulphide-linked Mr-225 000 peptide appeared heterogeneous, with pI of 5.6-6.0, and was considered to represent fibronectin. All major peptides were of non-collagenous nature, on the basis of their susceptibility to pepsin and resistance to collagenase. Purified myomedial basement-membrane-like material contained collagenous peptides, as indicated by the presence of hydroxyproline and hydroxylysine. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of pepsin-treated and reduced basement-membrane-like material revealed five high-molecular-weight collagenous components appearing in the Mr range 105 000-375 000 relative to type I collagen standards.

scholarly journals Characterization of the extracellular haemoglobins of Artemia salina

1977 ◽  
Vol 165 (1) ◽  
pp. 111-119 ◽  
Author(s):  
L Moens ◽  
M Kondo
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Sodium Dodecyl ◽  
Artemia Salina ◽  
Molecular Structures ◽  
Prolonged Incubation ◽  
Preferential Cleavage ◽  
Minimal Molecular Weight

The following factors were measured for extracellular haemoglobins of Artemia salina: a minimal molecular weight of globin chain per haem group (based on the iron and haem contents), the absorption coefficients, the absorption spectra of various derivatives and the amino acid compositions. These were compared with those of the haemoglobins of other invertebrates. Three Artemia haemoglobins (I, II and III) had similar molecular structures, constructed from two-globin subunits of 122000-130000mol.wt. Since the minimal mol.wt. was determined to be 18000, this suggests that one globin subunit was bound by seven haem groups, and hence one haemoglobin molecule (240000-260000mol.wt.) should contain 14 haem groups. A successful identification of this high-molecular-weight subunit required first the denaturation of haemoglobin in 1% sodium dodecyl sulphate before sodium dodecyl sulphate gel electrophoresis. Denaturation by prolonged incubation (12-36 h) at room temperature in the presence of 0.1% sodium dodecyl sulphate [Bowen, Moise, Waring & Poon (1976) Comp. Biochem. Physiol. B55, 99-103] was accompanied by extensive proteolysis, resulting in low recovery of the stainable protein and heterogeneous gel patterns. Regardless of which electrophoretic system was used, the high-molecular-weight subunit was always present provided that 1% sodium dodecyl sulphate was present during denaturation. These results contrast with those obtained by Bowen et al. (1976). However, preferential cleavage of the globin subunit (alpha) seemed to occur in vitro when standard conditions were used, producing two specific fragments having mol.wts. of 80000 (beta) and 50000 (gamma).

Interaction of sodium dodecyl sulphate with a soluble keratin

1956 ◽  
Vol 9 (2) ◽  
pp. 212 ◽  
Author(s):  
IJ O'Donnell ◽  
EF Woods
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Sodium Dodecyl ◽  
Relative Viscosity ◽  
Protein Molecules ◽  
Positive Groups

Electrophoretic studies have shown that sodium dodecyl sulphate combines with α-keratose in solution in amount far in excess of that required for stoichiometric binding to the positive groups on the protein. However, an amount equivalent to the number of positive sites on the protein is more firmly bound than the remainder. The variation of the relative viscosity and sedimentation coefficients with the amount of sodium dodecyl sulphate present on the protein has been attributed to changes in the configuration and state of aggregation of the protein molecules. A molecular weight of approximately 48,000 has been determined for a-keratose in the presence of sodium dodecyl sulphate.

scholarly journals ‘Tanned’ gelatin spheres and granules for exclusion chromatography

1968 ◽  
Vol 108 (4) ◽  
pp. 641-646 ◽  
Author(s):  
A. Polson ◽  
W. Katz
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
High Molecular Weight ◽  
Weight Fraction ◽  
High Flow ◽  
High Molecular Weight Fraction ◽  
Flow Rates ◽  
Protein Molecules ◽  
Exclusion Chromatography

1. The preparation of tanned gelatin spheres and granules from high-molecular-weight gelatin is described. This material is comparatively hard, giving high flow rates, is insoluble in water at temperatures between 0° and 100° and is resistant to digestion by trypsin and chymotrypsin. The high-molecular-weight fraction of gelatin was prepared by precipitation with polyethylene glycol, and the spheres and granules prepared from this fraction were hardened and insolubilized by tanning with either formalin or chromium salts or both. 2. The spheres and granules were used successfully for the separation of protein molecules and other protein-aceous materials ranging in molecular weight from 200 to greater than 6000000. This gel exclusion material has several properties superior to those of other products used for similar purposes. Further, it was noticed that the porosity of the spheres differed considerably from that of the granules.

Sign in / Sign up

Export Citation Format

Share Document