Essentials of biorecognition: The (strept)avidin–biotin system as a model for protein–protein and protein–ligand interaction

Molecular recognition or biorecognition is as the heart of all biological interactions. These interactions are characterized by a collection of noncovalent bonds, namely ionic, hydrogen-bonding and hydrophobic interactions. In addition, shape complementarity appears to play a pivotal role in the process of biorecognition. In this review, we examine the versatile avidin–biotin complex as a model system for study of the biorecognition phenomenon with respect to protein–protein, protein–peptide, protein–ligand and protein–DNA interactions.