denaturácia

Denaturácia is a process that alters the natural three-dimensional structure of a molecule, most commonly a protein or nucleic acid. This alteration is usually caused by external factors such as heat, acid, alkali, or mechanical agitation. When a protein denatures, its complex folded structure unravels, often exposing the hydrophobic interior to the aqueous environment and leading to aggregation. This loss of specific three-dimensional shape typically results in the loss of the molecule's biological function. For instance, cooking an egg causes the proteins in the egg white to denature, turning the liquid clear albumen into a solid white mass. Similarly, the denaturation of enzymes by high temperatures prevents them from catalyzing their specific reactions. Nucleic acids like DNA can also be denatured, for example, by heating, which breaks the hydrogen bonds holding the two strands together, causing them to separate. While denaturation is often irreversible, in some cases, particularly with mild treatments, the molecule can refold into its original conformation upon removal of the denaturing agent, a process known as renaturation.