lac operon

The lac operon is an operon required for the transport and metabolism of lactose in Escherichia coli and some other enteric bacteria. It consists of three adjacent structural genes, a promoter, a terminator, and an operator. The lac operon is regulated by several factors including the availability of glucose and of lactose. Gene regulation of the lac operon was the first genetic regulatory mechanism to be elucidated and is often used as the canonical example of prokaryotic gene regulation.
See more at Wikipedia.org...

Lac operon the lactose operon, a nucleotide sequence in Escherichia coli that controls the synthesis of the enzyme ß-galactosidase comprising [more]Lac operon - Community and Resources

A structural unit in the E.coli genome that consists of three structural genes (encoding different enzymes involved in sugar metabolism) transcribed together and their common promoter and operator genes. Provides a good model for studying the interactions between promoters and repressors.