Small-Angle Neutron Scattering Study of Micelle Structure in Protein-Detergent Complexes

Small-angle neutron scattering measurements have been carried out on micellar solutions of the detergent sodium dodecyl sulfate (SDS) and its complexes with the protein Bovine Serum Albumin (BSA) in aqueous solutions. It is found that the structure of micelle-like clusters bound to the protein in protein-detergent complexes is different from that of normal micelles in the pure detergent solutions. In protein-detergent complexes, the micelle-like clusters tend to be spherical with a much smaller aggregation number (detergent molecules per micelle) than those in normal micelles, and they are independent of the shape and aggregation number of the micelles in the corresponding pure detergent solutions.