Operon

Sequence of nucleotides, or a series of consecutive genes in a bacterial chromosome that share a common promoter are regulated by a common operator and expressed at the same time. These genes encode mostly enzymes involved in one metabolic pathway.

Types of operons

 * catabolic (inductive type): the presence of a substance that determines its activity has an inductive effect (triggers transcription), e.g. Lac operon


 * anabolic (repressive type): the presence of a substance determining its activity inhibits transcription, e.g. an operon for the synthesis of amino acids (histidine)

Related Articles

 * Operon model
 * Regulatory enzymes