Lac Operon
The lac operon is an operon required for the transport and metabolism of lactose in Escherichia coli and some other enteric bacteria. It consists of three adjacent structural genes, lacZ, lacY and lacA. The genes encode β-galactosidase, lactose permease, and thiogalactoside transacetylase (or galactoside O-acetyltransferase), respectively.
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