One of the continuing objectives of molecular biology research is to characterize the functronal domains of proteins. Many proteins contam domains capable of binding specific ligands, such as cofactors, substrates, and domains of other proteins, that form the basis for interactions that drive a large number of biological processes. Protein epitopes are a class of hgand binding domains responsible for eliciting an immune response; in this respect then identification can be of major importance in the development of vaccines and other pharmaceutical compounds.