A change in the molecular structure of globular proteins that may be induced by bringing a protein solution to its boiling point or by exposing it to acids or alkalies, or to various detergents. Denaturation reduces the solubility of proteins and prevents crystallization. It involves rupture of hydrogen bonds so that the highly ordered structure of the native protein is replaced by a looser and more random structure. It is usually irreversible but in some cases is reversible, depending on the protein and the treatment involved.Alteration of the specific native conformation of a polypeptide chain, protein, or nucleic acid. See Degradation.