Regulatory optical isomers

Enzymes are the most efficient and versatile catalysts known. They are able to increase the rates of some reactions by up to 14 orders of magnitude, with a high degree of specificity, such that they can not only distinguish between substrates, but also between two optical isomers of the same substrate. In addition, in biological systems they are normally subject to the regulatory action of cellular metabolites, such that they carry out diverse tasks while maintaining the overall chemical balance relatively constant. The reaction centre in the enzyme where the major chemical processes occur is known as the active site. The reactants involved in reactions catalysed by enzymes are known as snbstrates, and the compounds that increase or decrease the rates of these reactions are known as activators or inhibitors, respectively. 

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