Enzyme mechanism of action and Enzyme specificity
Enzymes and Enzyme specificity Enzyme , a substance that acts as a catalyst in living organisms, regulating the rate at which chemical reactions proceed without itself being altered in the process. Enzymes are giant macromolecules which catalyse biochemical reactions. They are remarkable in many ways. Their three-dimensional structures are highly complex, yet they are formed by spontaneous folding of a linear polypeptide chain. Their catalytic properties are far more impressive than synthetic catalysts which operate under more extreme conditions.The most striking characteristics of enzymes are their catalytic power and specificity. Catalysis takes place at a particular site on the enzyme called the active site. Nearly all known enzymes are proteins. The discovery of catalytically active RNA molecules provides compelling evidence that RNA was an early biocatalyst, the ribozyme. Most reactions in biological systems do not take place at perceptible rates in the absence of enzymes.