Question

Sodium dodecylsulfate (SDS) is an ionic detergent. At high concentrations, it completely denatures a protein whether it is a soluble or membrane protein. It is for this reason that SDS is routinely used in SDS-polyacrylamide gel electrophoresis (SDS-PAGE) to allow the molecular weight of a protein to be accurately determined. Explain why SDS is a good detergent that can completely solubilize membrane proteins

Answer 1

At high concentrations, the polar region (hyrophyllic) is exposed towards the solvent (water) molecules and the the non polar (Hydrophobic) region comes together in the interior for the formation of SDS Micelle. While the charged region interacts with the water molecules, the hydrophobic region interacts with the non polar residues of proteins resulting in a soluble protein - detergent complex.

Thus SDS will denature secondary and tertiary structures so that the protein becomes more soluble.