Lac operon

lac operon

A set of genes in E. coli's genome involved in the metabolism of lactose.

lactose

A sugar found in milk that the lac operon helps metabolize.

lacZ gene

A gene in the lac operon that codes for an enzyme that cleaves lactose into simpler sugars.

lacY gene

A gene that codes for an enzyme allowing for the absorption of lactose through cellular membranes.

lacA gene

A less understood gene in the lac operon that contributes to lactose metabolism.

promoter

A region where RNA polymerase attaches to initiate transcription in the operon.

operator

A site in the operon where the lac repressor can bind to inhibit transcription.

lac repressor

A protein that binds to the operator and prevents transcription when lactose is not present.

Allolactose

An isomer of lactose that acts as an inducer of transcription by binding to the lac repressor.

Catabolite Activator Protein (CAP)

A protein that activates transcription in the presence of Cyclic AMP when glucose is low.

Cyclic AMP (cAMP)

A molecule that indicates low glucose levels and activates the Catabolite Activator Protein.

transcription

The process of copying a segment of DNA into RNA, which occurs when the lac repressor is not bound.

inducer

A molecule that initiates gene transcription by preventing the repressor from binding to the operator.

E. coli

A bacterium that utilizes the lac operon to metabolize lactose in its environment.