Non-competitive inhibition occurs when the inhibitor binds to which site?

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Multiple Choice

Non-competitive inhibition occurs when the inhibitor binds to which site?

Non-competitive inhibition works by the inhibitor attaching to a site on the enzyme that is not the active site, an allosteric site. This binding changes the enzyme’s shape in a way that the active site can’t catalyze the reaction efficiently, even when substrate is abundant. Because the inhibitor isn’t competing with the substrate for the active site, increasing substrate concentration doesn’t fully restore activity. This distinguishes it from competitive inhibition, where the inhibitor blocks the active site itself. It isn’t about binding to the substrate or to the product as the mechanism. The overall result is a lower maximum reaction rate (Vmax), while substrate affinity (Km) is typically unaffected in pure non-competitive inhibition.

Non-competitive inhibition works by the inhibitor attaching to a site on the enzyme that is not the active site, an allosteric site. This binding changes the enzyme’s shape in a way that the active site can’t catalyze the reaction efficiently, even when substrate is abundant. Because the inhibitor isn’t competing with the substrate for the active site, increasing substrate concentration doesn’t fully restore activity. This distinguishes it from competitive inhibition, where the inhibitor blocks the active site itself. It isn’t about binding to the substrate or to the product as the mechanism. The overall result is a lower maximum reaction rate (Vmax), while substrate affinity (Km) is typically unaffected in pure non-competitive inhibition.

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