Sodium dodecyl sulphate protein binding

While studying the binding of mercury by chromatin of rats injected with mercuric chloride, the nonhistone chromatin proteins in rat and kidney cell nuclei were shown to be mainly responsible for the mercury deposition [43]. The mercury-binding nonhistone proteins were found to be heterogeneous by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. 

The major components of beef glomerular basement membrane were solubilized with sodium dodecyl sulphate and resolved on 6% agarose [229]. 0.1% SDS has also been used in the separation of lipoprotein and apolipoprotein from human plasma [230] and 3% SDS used in gel chromatography of human erythrocyte membranes on Sepharose 6B [231]. Stokes radius determination of insulin-binding protein was performed on Sepharose 6B with 0.5% Triton X-100 [232]. 

This method is based on the binding of hydrophobic markers to the protein molecule, while the adsorbed quantity is used as a measure for hydrophobicity. This molecule can be a simple aliphatic molecule such as hexan [20-25] or triglyceride [26,27] or even a surfactant such as sodium dodecyl sulphate [28-30],... 

Pitt-Rivers R, Ambesi Impiombato FS. The binding of sodium dodecyl sulphate to various proteins. Biochem J 1968 109 825-829. 

Sodium dodecyl sulphate is bound co-operatively to most protein, the critical concentration for co-operative binding being about 25 % of the CMC. Non-ionic surfactants and the bile salts do not usually induce co-operative binding and do not usually, therefore, denature proteins, although dissociation into inactive or... 

In the presence of sodium dodecyl sulphate, the BSA (which has about 70 binding sites for SDS, 10-11 of which showing larger affinity than the others) undergoes a biphasic denaturation two endotherms appear in the DSC trace which are related to protein denaturation and binding equilibrium, respectively, (rather than to denaturation of different protein domains) [199]. 

The polypeptides of the light-harvesting complex are most easily resolved by polyacrylamide gel electrophoresis of thylakoid membranes solubilized with sodium or lithium dodecyl sulphate. This produces the green chlorophyll-protein band, CP II, which on staining for protein reveals up to four polypeptides of 24-27 kDa [2], each of which is believed to bind Chi a and Chi b. In most plants two polypeptides predominate, but other minor polypeptides may be resolved [2]. 

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