Lesson 4: Inhibitors

Question 1

What is Enzyme Inhibition?

Answer 1

When the action of an enzyme is slowed down or stopped by the action of another substance

Question 2

What is a Competitive Inhibitor?

Answer 2

-Similar shape to the enzymes substrate
-Compete with substrate for access to active site
-Bind to the active site forming an enzyme-inhibitor complex making enzyme catalytically inactive
-Removes number of active sites so slows reaction
-If done in revers called an inactivator

Question 3

What is a Non-Competitive Enzyme?

Answer 3

-Doesn’t resemble shape of enzymes substrate as they don’t enter active site
-Join enzyme at differnet point called allosteric site
-Disrupts the tertiary structure of an enzyme cause ong active site to distort
-Can be reversible or irreversible

Question 4

Example of Competitive Inhibtor

Answer 4

Penicillin
-Blocks active site of enzyme that is needed for bacterial walls so bacteria can’t multiply

Question 5

Example of Non-Competitive Inhibtor

Answer 5

Non-Competitive inhibition of acetylcholinesterase by organophosphate insecticides

Question 6

Metabolic Pathways

Answer 6

-Many metabolic processes in the body have sequences of enzyme-catalysed reactions, with the product of one becoming the substrate for the next
-The product of the last reaction normally binds to the first enzyme in the reaction, which temporarily inhibits the enzyme
-This prevents accumulation of too much end product