Enzyme Inhibition

Question 1

Ways that an enzyme can be inhibited

Answer 1

• Competitive
• Non-competitive
• Irreversible/poison

Question 2

How are most enzymes are inhibited?

Answer 2

Competitive

Question 3

Inhibition of allosteric enzymes and hemoglobin

Answer 3

Non-competitive

Question 4

Where does the competitive enzyme inhibitor bind?

Answer 4

Active (catalytic) site

Question 5

Reversible enzyme inhibitors

Answer 5

• Competitive
• Non-competitive

Question 6

Shape of molecule of competitive enzyme inhibitor

Answer 6

S

Question 7

Competitive inhibitor effect on Vmax

Answer 7

None

Question 8

Competitive inhibitor effect on Km

Answer 8

Increase

Question 9

Where does the non-competitive inhibitor bind?

Answer 9

Allosteric site

Question 10

Non-competitive inhibitor effect on Vmax

Answer 10

Decreases

Question 11

How are the kinetics of non-competitive inhibitors explained?

Answer 11

Hill equation/plot

Question 12

Examples of irreversible or poison enzyme inhibition

Answer 12

• Heavy metals (silver, mercury)
• Nerve gas
• Carbon monoxide
• Cyanide

Question 13

What equation is associated with allosteric regulation?

Answer 13

Hill equation (plot)

Question 14

What does it mean if the Hill coefficient (H) is greater than 1? What if it is less than 1?

Answer 14

• Greater than 1: Positively cooperative
• Less than 1: Negatively cooperative