Comparison between Competitive Inhibitor and Non-Competitive Inhibitor
Let me share with you a comparison between Competitive Inhibitor and Non-Competitive Inhibitor.
Aspect | Competitive Inhibitor | Non-Competitive Inhibitor |
Binding Site on enzyme | Binds to the active site of the enzyme. | Binds to a site other than the active site (allosteric site). |
Competition with substrate | Competes with the substrate for the active site. | Binds to the enzyme-substrate complex or the enzyme itself without competing with the substrate. |
Effect on Enzyme-Substrate Complex | Prevents the formation of the enzyme-substrate complex. | Alters the shape of the enzyme or active site, making it less effective in catalyzing the reaction. |
Reversibility | Reversible inhibition | Often irreversible inhibition |
Enzyme Activity | Enzyme activity can be restored by increasing substrate concentration. | Enzyme activity cannot be fully restored by increasing substrate concentration. |
Graphical Representation | In the presence of a competitive inhibitor, the Vmax remains the same, but Km increases. | In the presence of a non-competitive inhibitor, both Vmax and Km are altered. |
Examples | Malonate inhibiting succinate dehydrogenase in the citric acid cycle. | Cyanide inhibiting cytochrome c oxidase in the electron transport chain. |