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Biological processes depend on a steady flow of energy and the production of specific molecules. For most reactions, the energy required to bring reactants together—known as activation energy—is often too high for spontaneous occurrence. Enzymes lower this barrier, enabling reactions to proceed at rates compatible with life.
At moderate temperatures, increased kinetic energy can accelerate enzyme activity. However, when temperatures rise beyond an enzyme’s optimal range, the delicate three‑dimensional fold that defines its active site is compromised, leading to reduced catalytic efficiency.
Heat‑induced denaturation disrupts the non‑covalent interactions that hold an enzyme’s tertiary structure together. Although the protein chain remains intact, its shape changes irreversibly in most cases, preventing proper substrate binding.
Enzymes exhibit exquisite specificity, recognizing only particular substrates. When either the enzyme or the substrate becomes denatured, the fit between the two is lost, halting the reaction. This principle explains why cooking denatures proteins, making them easier to digest.
