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AAT Bioquest

In what ways does a competitive inhibitor differ from a noncompetitive inhibitor?

Posted January 16, 2024


Answer

A competitive inhibitor and a noncompetitive inhibitor bind to different sites on the enzyme. Competitive inhibitors bind to the active site of the enzyme, competing directly with the substrate for binding. Noncompetitive inhibitors bind to an allosteric site on the enzyme distinct from the active site, altering the enzyme's conformation and function. Thus the enzyme shifts from its ideal position, resulting in its reduced efficiency in catalyzing the reaction. Another way they are similar is in regard to substrate binding. Competitive inhibitors often mimic the structural features of the enzyme's natural substrate, allowing them to bind strongly to the active site. A non-competitive inhibitor typically doesn't share a structural similarity with the substrate as it binds to the allosteric site.

Additional resources

Enzymes

Amplite® Fluorimetric Coenzyme A Quantitation Kit *Green Fluorescence*