Physicochemical studies of dinitrophenylated bovine serum albumin

The structural changes of bovine serum albumin (BSA) as a function of dinitrophenylation have been studied by disc gel electrophoresis, sedimentation velocity analyses, and circular dichroism. These experiments were designed to understand the molecular bases for the change in immunogenicity and antigenicity of BSA upon dinitrophenylation. Dinitrophenylated BSA tends to aggregate to dimers and higher aggregates. A concomitant large change in electrophoretic mobility was also observed. Circular dichroism studies reveal a large decrease in the alpha-helical structure of the BSA molecule.