What Is Lac Operon System

The lactose operon (lac operon) is an operon required for the transport and metabolism of lactose in E. coli and many other enteric bacteria. … This lactose metabolism system was used by François Jacob and Jacques Monod to determine how a biological cell knows which enzyme to synthesize.

What is lac operon?

Structure of the lac operon The lac operon contains three genes: lacZ, lacY, and lacA. These genes are transcribed as a single mRNA, under control of one promoter. Genes in the lac operon specify proteins that help the cell utilize lactose.

What is lac operon explain with diagram?

Lac operon contains genes involved in metabolism. The genes are expressed only when lactose is present and glucose is absent. The operon is turned on and off in response to the glucose and lactose levels: catabolite activator protein and lac repressor. The lac repressor blocks the transcription of the operon.