Antigenic determinants in proteins coincide with surface regions accessible to large probes (antibody domains)

摘要: Abstract We evaluated surface areas on proteins that would be accessible to contacts with large (1-nm radius) spherical probes. Such spheres are comparable in size antibody domains contain antigen-combining sites. We found all the reported antigenic sites correspond segments particularly a sphere. The were also evident as most prominently exposed regions (hills and ridges) contour maps of solvent-accessible (small-probe) surface. In myoglobin cytochrome c, virtually van der Waals is probe therefore potentially antigenic; myohemerythrin, distinct large-probe-inaccessible, nonantigenic, apparent. correlation between large-sphere-accessibility antigenicity myoglobin, lysozyme, c appears better than exist segmental flexibility; is, rigid often constitute epitopes, whereas some flexible parts molecules do not appear antigenic. propose primary reason why certain polypeptide-chain their exceptional exposure, making them readily available for Exposure these frequently results high mobility and, consequence, flexibility.