An inhibitor resembling the substrate binds the active site and can be overcome by more substrate.
The inhibitor competes with the substrate for the active site, so Km appears to increase while Vmax stays the same. High substrate concentration can outcompete it.
Many drugs act this way.
An inhibitor resembling the substrate binds the active site and can be overcome by more substrate.
Competitive Inhibition is one of the 51 topics in Biomolecules & Biochemistry. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Michaelis-Menten Kinetics, Noncompetitive Inhibition, Induced Fit Model.
Statins resemble HMG-CoA and inhibit cholesterol synthesis; methotrexate competes for dihydrofolate reductase.
Work through the Beginner topics in Biomolecules & Biochemistry first, such as Water Properties, Carbon Chemistry, Carbohydrates, then return to Competitive Inhibition. Intermediate topics assume the Beginner vocabulary.
The closest topics to Competitive Inhibition are Michaelis-Menten Kinetics, Noncompetitive Inhibition, Induced Fit Model, Active Site. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Competitive Inhibition. To practise the whole of Biomolecules & Biochemistry, use the Biomolecules & Biochemistry quiz.
Competitive Inhibition: An inhibitor resembling the substrate binds the active site and can be overcome by more substrate. Michaelis-Menten Kinetics: Models reaction velocity as Vmax times substrate over Km plus substrate, describing enzyme saturation. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Michaelis-Menten Kinetics and explain the difference aloud. Finally, take the Biomolecules & Biochemistry quiz and come back to this page for any question you miss.
Models reaction velocity as Vmax times substrate over Km plus substrate, describing enzyme saturation.
⚗️ Biomolecules & BiochemistryAn inhibitor binds elsewhere on the enzyme, lowering Vmax without changing Km.
⚗️ Biomolecules & BiochemistrySuggests the enzyme's active site changes shape slightly as the substrate binds, improving the fit.
⚗️ Biomolecules & BiochemistryThe specific pocket on an enzyme where the substrate binds and the reaction takes place.
⚗️ Biomolecules & Biochemistry