Lac operon: Learn about the lac

Learn about the lac operon , a group of genes involved in lactose metabolism in bacteria. Find out how it is regulated by lactose, glucose, and other factors, and see diagrams of its structure and function. Basic lac Operon structure E. coli encounters many different sugars in its environment. These sugars, such as lactose and glucose, require different enzymes for their metabolism. Three of the enzymes for lactose metabolism are grouped in the lac operon : lacZ, lacY, and lacA (Figure 12 1 1). LacZ encodes an enzyme called β-galactosidase, which digests lactose into its two constituent sugars: glucose and galactose. lacY is a permease that helps to transfer lactose into the cell. Finally, lacA ... The lac operon of E. coli is the hypothesis for gene regulation; the key component is the lacI repressor. The uncontrolled-type DNA sequence of lac operon has three lac repressor recognition sites in a stretch of 500 base pairs. It also has a binding site for catabolite activator proteins (CAP), which is considered to be an activator. Lac Operon “ Lac operon is an operon or a group of genes with a single promoter that encode genes for the transport and metabolism of lactose in E.coli and other bacteria.”