scholarly journals Polymeric structure of a high-molecular-weight glycoprotein from bovine cervical mucus

1983 ◽  
Vol 215 (3) ◽  
pp. 701-704 ◽  
Author(s):  
F A Meyer

A 16 X 10(6)-Mr glycoprotein isolated from bovine oestrus cervical mucus when reduced under conditions where disulphide-bond cleavage is essentially quantitative produces chains whose Mr from light-scattering and from sedimentation and diffusion data is some 4 X 10(6)-5 X 10(6). Pronase digestion of the chains indicates that glycosylated sequences of Mr 0.3 X 10(6)-0.5 X 10(6) are interspersed with enzyme-susceptible non-glycosylated peptide sequences.

2015 ◽  
Vol 11 (8) ◽  
pp. 3866-3872
Author(s):  
E.A. Masimov ◽  
Etibar Hummat Ismailov ◽  
S.Y. Odzhaqverdiyeva

Dynamic light scattering (DLS) method in combination with the UV/VIS spectrophotometry is used to study the interaction of polyethylene- glycols with a molecular weight  6000 ( PEG6000 ) with sodium salts of citric and succinic acids in aqueous solutions. The values of density, viscosity, refractive and diffusion indexes, the values of the hydrodynamic diameter, wavelength electronic absorption bands for PEG6000 aqueous solutions, their mixtures with succinic and citric acids are determined. It was shown that depending on the composition of the solutions the values of hydrodynamic diameter for aqueous solutions containing 1-5 wt.% PEG6000 and their mixtures with succinic and citric acids (~ 1 wt%) ranges from 3.6 to 5.2 nm. It is assumed that the formation of complexes with the sizes  that are within the above range is due to the features of interaction  and the structure of the complexes formed in solution.


1962 ◽  
Vol 40 (1) ◽  
pp. 877-883 ◽  
Author(s):  
J. P. Kratohvil ◽  
W. G. Martin ◽  
W. H. Cook

Solutions of α-lipovitellin in 1 M formic acid and 0.01 M hydrochloric acid had two sedimenting components of ca. 2.0 S and 4.6 S. Initially, acid solutions of β-lipovitellin contained only the 4.6 S component but, after about 4 days, the 2.0 S component was also present. Using freshly prepared solutions the molecular weight (M) of this 4.6 S component of β-lipovitellin was established as 3.9 × 105 by both light scattering and sedimentation and diffusion measurements. This component appears, therefore, to be the associated form of β-lipovitellin of 11 S and M = 4.0 × 105 in neutral solvents. The 2.0 S component must therefore be a dissociated subunit of comparable or smaller size than the subunit of 7 S and M = 2.0 × 105 in alkaline solvents. Evidently both lipovitellins dissociate in acid, as they do in alkaline solvents, but the solubility behavior and irreversible changes that occur in acid precluded a quantitative study.


1968 ◽  
Vol 109 (4) ◽  
pp. 517-526 ◽  
Author(s):  
M B Mathews ◽  
L. Decker

1. The effects of acid mucopolysaccharides and acid mucopolysaccharide–proteins on the size and rate of formation of fibril aggregates from collagen solutions in pH7·6 buffers were studied by turbidimetric and light-scattering methods. 2. Serum albumin, orosomucoid, methylated cellulose, chondroitin sulphate A and chondroitin sulphate C of molecular weight less than 20000, and hyaluronate of molecular weight less than 40000 did not influence rates of fibril formation. Chondroitin sulphate A, chondroitin sulphate C and hyaluronate of high molecular weight retarded the rate of fibril formation. This effect of high-molecular-weight chondroitin sulphate C decreased with increasing ionic strength. Heparin, though of low molecular weight (13000), was highly effective, as was also heparitin sulphate. The chondroitin sulphate–proteins of very high molecular weight were highly effective, despite the fact that for some preparations the component chondroitin sulphate chains had molecular weights much less than 20000. 3. Agents that had delayed fibril formation were also effective in producing an increase in degree of aggregation of fibrillar collagen, as indicated by dissymmetry changes observed in light-scattering experiments at low collagen concentrations. Methylated cellulose and heparin at 2·5μg./ml. were unusual in decreasing aggregation, but heparin at 0·25μg./ml. increased aggregation. Electron microscopy of gels showed fibrils and fibril aggregates with ‘normal’ collagen spacing and dimensions consistent with the light-scattering results. 4. The rates of electrical transport of agents and of solvent (electro-osmosis) through collagen gels indicated a contribution of molecular entanglement that increased with increase in molecular size of the agents. Electrostatic binding of heparin to collagen was noted. Binding to collagen during fibril formation was also found for heparitin sulphate and a chondroitin sulphate with extra sulphate groups. 5. Electrostatic binding of acid mucopolysaccharide–proteins to collagen may be an important factor in the organization and functioning of connective tissues at all stages of growth and development. Excluded-volume (molecular-entanglement) effects may also be important. These factors operate simultaneously and interact mutually so that precise assessment of their relative importance is difficult.


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