Classification and Nomenclature of Enzymes
Enzymes are biological catalysts that facilitate biochemical reactions in living organisms. A vast number of enzymes have been identified, and they are systematically classified into six main categories based on the type of reaction they catalyze. The classes are defined as follows:
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Oxidoreductases/Dehydrogenases: These enzymes catalyze oxidation-reduction reactions involving the transfer of electrons between substrates. For instance, if a substrate 'S' is reduced, another substrate 'S'' becomes oxidized.
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Transferases: These enzymes are responsible for transferring functional groups (G) from one substrate to another, altering their composition. For example, the reaction could involve two substrates where a group is removed from one and added to another.
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Hydrolases: Enzymes in this class catalyze hydrolysis reactions, breaking down various bond types including ester, ether, peptide, and glycosidic bonds by introducing water.
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Lyases: These enzymes remove groups from substrates through mechanisms other than hydrolysis, resulting in the formation of double bonds.
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Isomerases: This class includes enzymes that facilitate the interconversion of isomers, helping in the rearrangement of the molecular structure of substrates.
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Ligases: Enzymes categorized as ligases catalyze the joining of two compounds (like C-O, C-N bonds), often involving coupling reactions that require energy.
Each enzyme class is assigned a four-digit number for precise identification, enabling researchers to catalog and study specific enzymes efficiently. This classification system not only aids in understanding the diverse functions of enzymes in different metabolic processes but also establishes a framework for enzyme research and application in biotechnology.