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. Regulation of genes for lactose utilization. lac repressor, catabolite activator protein, and cAMP. Learn about the lac operon , its structure, role, and example for quick understanding. Key for Class 12 biology students.
