What characterizes irreversible inhibitors?

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Multiple Choice

What characterizes irreversible inhibitors?

Irreversible inhibitors permanently disable an enzyme by forming a covalent bond with a residue on the enzyme, usually at or near the active site. This covalent modification changes the enzyme’s structure or blocks key catalytic groups, so the enzyme cannot catalyze reactions again. Because covalent bonds are not easily broken under physiological conditions, the only way to regain activity is for the cell to synthesize new enzyme molecules. In contrast, non-covalent binding to the enzyme or reversible binding to the active site can be undone when the inhibitor dissociates, so those forms of inhibition are not permanent. Binding to the substrate alone does not modify the enzyme itself and therefore does not constitute irreversible inhibition.

Irreversible inhibitors permanently disable an enzyme by forming a covalent bond with a residue on the enzyme, usually at or near the active site. This covalent modification changes the enzyme’s structure or blocks key catalytic groups, so the enzyme cannot catalyze reactions again. Because covalent bonds are not easily broken under physiological conditions, the only way to regain activity is for the cell to synthesize new enzyme molecules.

In contrast, non-covalent binding to the enzyme or reversible binding to the active site can be undone when the inhibitor dissociates, so those forms of inhibition are not permanent. Binding to the substrate alone does not modify the enzyme itself and therefore does not constitute irreversible inhibition.

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