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Metabolic pathwaysNon-competitive inhibition

Metabolism refers to all of the chemical reactions that take place inside living cells. Unicellular and multicellular organisms must control their metabolism in order to survive.

Part of Human BiologyHuman Cells

Non-competitive inhibition

This occurs when:

  • an inhibitor does not bind to the active site but binds to a different part of the enzyme
  • this changes the active site shape
  • this stops the substrate binding to the enzyme and decreases the reaction rate
Substrate can鈥檛 bind because competitive inhibitor prevents it accessing active site.  Non-competitive inhibitor embedded in bottom of enzyme. Active site altered so substrate still can鈥檛 bind.

Non-competitive inhibition cannot be reversed by increasing the substrate concentration.

Examples of non-competitive inhibitors include cyanide, mercury and silver.