Term: enzyme repression
https://doi.org/10.1351/goldbook.E02158

Definition:
The mode by which the synthesis of an enzyme is prevented by repressor molecules. In many cases, the end product of a synthesis chain (e.g. an amino acid) acts as a feed-back corepressor by combining with an intracellular aporepressor protein, so that this complex is able to block the function of an operator. As a result, the whole operon is prevented from being transcribed into mRNA, and the expression of all enzymes necessary for the synthesis of the end product amino acid is abolished.

Related Terms:
1) mode (http://doi.org/10.1351/goldbook.M03958).
2) block (http://doi.org/10.1351/goldbook.B00682).
3) enzymes (http://doi.org/10.1351/goldbook.E02159).
4) repressor (http://doi.org/10.1351/goldbook.R05304).
5) operon (http://doi.org/10.1351/goldbook.O04301).

Source: PAC, 1992, 64, 143. 'Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)' on page 152 (https://doi.org/10.1351/pac199264010143)

Citation: 'enzyme repression' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.E02158

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