Mapping protein-protein interactions with combinatorial biology methods

Extremely diverse, DNA-encoded libraries of peptides and proteins have been constructed that include a linkage between each polypeptide and the encodi ng DNA. Library members can be selected by virtue of a particular binding s pecificity, and their protein sequence can be deduced from the sequence of the cognate DNA. Such combinatorial biology methods have proven invaluable in both identifying natural protein-protein interactions and also in mappin g the specificities and energetics of these interactions in fine detail.