Enzyme Inhibition Flashcards
What is an inhibitor?
A substance which decreases the rate of an enzyme controlled reaction, is effect can be permanent or temporary
What is competitive inhibition?
It is temporary
The inhibitor is a similar shape to the complimentary binding site of the substrate so it binds to the active site
It is unreactive as it has a different structure but it blocks the active site so it cannot be used by substrate
What affect does competitive inhibition have on the reaction rate?
The substrates are now competing with inhibitors so as a result fewer substrates can bind to active sites so reaction rate decreases
How to increase the chances of substrates colliding rather than inhibitors in the case of competitive inhibition?
Increase substrate concentration
What is non-competitive inhibition?
Can be reversible and irreversible
The inhibitor does not bind to the active site instead it binds to a non-active allosteric site where it changes the shape of the active site indirectly
What affect does non-competitive inhibition have on reaction rate?
Reaction rate decreases because the active site can you longer bind to substrates to create products as enzymes are specific and altering the shape of the active sites means that they cannot bind
How to decrease effect of non-competitive inhibition?
It is not affected by substrate concentration because no substrate can bind so increasing the substrate concentration doesn’t make any difference
What is feedback inhibition?
Reversing condition or stopping something happening. Product inhibits original enzyme in pathway to stop too much product being produced
