Comparative properties of two peptide-antibody interactions as deduced from epitope delineation

The linear epitope recognized by three closely related antibodies specific for the E6 oncoprotein of papillomavirus type 16 was delineated by phage display, spot peptide synthesis on cellulose membranes, and kinetic measurements with antigenic variants using a BIACORE. The same approaches, recently applied to an antibody specific for tobacco mosaic virus protein, led to the clear-cut delineation of a functional epitope comprising four key positions with well defined physico-chemical properties. In contrast, the E6 system is characterized by a non-essential contribution to binding of various factors, so that combinations of alternative properties are compatible with measurable binding activity.