Enzyme Inhibition Flashcards
What are competitive inhibitors
They have similar shape to that of substrate molecules
They compete with the substrate to bind to the active site but no reaction takes place
Instead they block the active site, so no substrate molecules can fit in
What does it depend on how much the enzyme is inhibited
On concentration of inhibitor and substrate
If there’s a high concentration of inhibitor, it will take up nearly all the active sites and hardly any substrate will get to the enzyme
But if there’s a higher concentration of substrate, then the substrates chances of getting to an active site before the inhibitor increase. So increasing concentration of substrate will increase the rate of reaction
What’s a non competitive inhibitor
They bind to the enzyme away from its active site - causes active site to change shape so substrate molecules can no longer bind to it
They don’t compete with the substrate molecule to bind to the active site because they are a different shape
What will increasing the concentration of substrate do in non competitive inhibitor
Nothing on rate of reaction - enzyme activity will still be inhibited
an enzyme controlled reaction is inhibited by substance X. suggest a simple way in which you could tell whether substance X is acting as a competitive or non competitive inhibitor
increase the substrate concentration. If the degree of inhibition is reduced, it is a competitive inhibitor if it stays the same it is non competitive
