1.9 enzyme inhibition

Question 1

What are enzyme inhibitors

Answer 1

Substances that directly or indirectly interfere with the functioning of the active site of an enzyme and so reduces its activity

Question 2

What are competitive inhibitors

Answer 2

Competitive inhibitors have a shape similar to a substrate. This allows them to bind to the active site and therefore compete with the substrate for the active site

Question 3

What determines the effect on the rate of reaction

Answer 3

The rate of reaction is determined by the concentration of substrate or inhibitor. This is because if there is an increase in substrate ESC are more likely to form then a inhibitor occupying the active site

Question 4

What is an example of competitive inhibitors

Answer 4

An example of competitive inhibitors occurs in respiratory enzyme that acts on succinate. A compound called malonate has similar shape and therefore blocks the succinate from the enzyme by forming a ESC with the enzyme

Question 5

Heo does a non competitive inhibitor affect enzymes

Answer 5

This is because a non competitive inhibitor attach themselves to a site which is not the active site and alter the shape of the enzyme and as a result the substrate can no longer bind to the the enzyme

Question 6

Why does an increase in substrate not affect non-competitive inhibitor

Answer 6

This is because they are not competing for the same active site and therefore an increase in substrate concentration does not decrease the affect of the inhibitor