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How does allosteric inhibition provide negative feedback in a metabolic pathway?

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Allosteric inhibition provides negative feedback in a metabolic pathway by regulating the activity of key pacemaker enzymes through the binding of an end product.1

In this process, a regulatory molecule—typically the end product of a biosynthetic pathway—binds to an allosteric site on the enzyme that is distinct from its catalytic active site. This interaction induces a conformational change in the enzyme's shape, which reduces its affinity for its substrate or otherwise diminishes its catalytic efficiency.213

By inhibiting the first unique step of a pathway, the cell ensures that it only synthesizes the amount of a product it currently requires. This negative feedback system allows for "fine control" of metabolism, where cellular concentrations of metabolites directly determine the rates of their own formation. This mechanism prevents the wasteful overproduction of substances and allows the cell to maintain metabolic balance in response to changing environmental conditions.12