Competitive inhibitors

Question 1

What is an inhibitor?

Answer 1

• A factor that prevents or reduces the rate of enzyme-catalysed reaction.

Question 2

What are Enzyme Inhibitors?

Answer 2

• Competitive or non-competitive
• Reversible or irreversible

Question 3

What are COMPETITIVE INHIBITORS?

Answer 3

• Similar shape to the substrate molecule
• They compete with the substrate to join on the enzyme active site.
• if they do this, not reaction takes place.
• they block the active site, so the substrate cannot join, reduces the rate of reaction.

Question 4

What are some examples of competitive inhibitors?

Answer 4

• Statins
• Aspirin

Question 5

How are statins used as competitive inhibitors?

Answer 5

• There are enzymes in the body that make cholesterol
• Statins are competitive inhibitors of these enzymes, reducing their activity, so less cholesterol is produced.

Question 6

How is aspirin used as competitive inhibitors?

Answer 6

• binds to the enzyme needed to make prostaglandins
• prostaglandins make our NS more sensitive to pain
• when aspirin stops the enzymes working, we are less sensntitive to pain.

Question 7

FEATURES of Competitive Inhibitors?

Answer 7

• Most of them are REVERSIBLE - they are temporarily attached to the enzyme
• HOWEVER, aspirin is IRREVERSIBLE - it is permanently attached to the enzyme.