What is meant by operon? Describe the expression process of Lac-operon of E. coli
Operon is a functioning unit of genomic DNA containing a cluster of genes under the control of a single promoter. The lac operon (lactose operon) is the operon required for the transport and metabolism of lactose in E. coli and many other enteric bacteria. Although lactose is the preferred carbon source for most bacteria, the lac operon allows for the effective digestion of lactose when glucose is not available. Gene regulation of the lac operon was the first genetic regulatory mechanism to be understood clearly, so it has become a foremost example of procariotic gene regulation.