Enzyme inhibitors Flashcards
What does an enzyme inhibitor do?
It reduces an enzymes activist and stops an E - S substrate from forming
What is a competitive inhibitor?
An inhibitor with the same shape as a substrate that binds to an enzymes active site
How does a competitive inhibitor work?
It binds to the enzymes active site because it has the same shape as the substrate, stopping the substrate from entering, reducing the number of enzyme substrate complexes being made and reducing the reaction rate
What happens to the reaction rate when more substrate is added with a competitive inhibitor?
The reaction rate increases because the enzyme is more likely to bind to the substrate than inhibitor
What happens to the reaction rate when more inhibitor is added with a competitive inhibitor?
The reaction rate decreases because the enzyme is more likely to bind to the inhibitor than the substrate, so less E-S complexes are made
What is a non reversible competitive inhibitor called?
An inactivator
What is a non competitive inhibitor?
An inhibitor that doesn’t attach to the allosteric site?
How does a non competitive inhibitor work?
It binds to the allosteric site that changes the enzymes tertiary structure and the enzymes active site so the substrate can no longer fit and the reaction rate decreases
What happens to the reaction rate when more inhibitor is added with a non competitive inhibitor?
The reaction rate decreases because the inhibitors bind to the enzyme so there are less available active sites for the substrate to react in
What happens to the reaction rate when more substrate is added with a non competitive inhibitor?
The reaction rate doesn’t change much because there will still be the changes in the active site
What are end product inhibitors?
After an enzyme catalysed a reaction, the product stays in the enzyme, stopping it from catalysing any more reactions
What is end product inhibition an example of?
Negative feedback
How do inhibitors control metabolic sequences?
They use the end product to inhibit the 1st enzyme of there is too much of the product being made
What does a reversible inhibitor do?
Reversible inhibitors don’t denature the enzyme, and weakly binds with to enzymes with H bonds
They can remove/ change coenzymes and cofactors
What does a non reversible inhibitor do?
It can’t be reversed, the enzyme is permanently denatured because the inhibitor covalently binds to the bond
