Allolactose, an isomer of lactose, is formed in small amounts from lactose. An E. coli cell is presented for the first time with the sugar lactose (containing allolactose) as a potential food source. Which of the following occurs when the lactose enters the cell?

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When lactose enters the E. coli cell, allolactose is formed in small amounts from lactose. Allolactose acts as an inducer by binding to the repressor protein, causing a conformational change that prevents it from binding to the operator. This allows RNA polymerase to transcribe the genes necessary for lactose metabolism, leading to the production of enzymes necessary for lactose breakdown.

Allolactose, an Isomer of Lactose, Is Formed in Small Amounts