Protein folding is the process by which a disordered protein chain attains its unique three-dimensional structure. Molecular recognition is the specific binding of molecules to each other. Most biological processes, such as enzyme catalysis, regulation of gene expression, or signal transduction in the cell, involve molecular recognition.
Molecular recognition is also important in the emerging field of supramolecular chemistry.
Protein folding and molecular recognition are closely related problems. The former is intramolecular and the latter intermolecular. Because both occur in solution, interaction with water plays a critical role in these processes. What controls the conformation of a protein or the relative configuration of two molecules in water is the effective energy, the sum of the intramolecular energy and the solvation free energy . Statistical thermodynamics of solvation Solvation by water plays a crucial role in both protein folding and molecular recognition.