Which proteins are encoded by the lac operon in E. coli?

The proteins encoded by the lac operon in E. coli are primarily involved in the transport and metabolism of lactose. The lac operon includes genes that encode for lactose permease, which facilitates the uptake of lactose into the bacterial cell, and β-galactosidase, which is responsible for breaking down lactose into glucose and galactose. This operon is crucial for E. coli when it is utilizing lactose as a carbon source, particularly in environments where glucose is scarce.

Understanding the function of the lac operon highlights the organism's ability to adapt its metabolism based on available nutrients, specifically targeting lactose as a source of energy when necessary. This is a fundamental example of gene regulation in response to environmental conditions in bacterial cells.