Enzyme Inhibition

Question 1

Competitive Inhibition

Answer 1

Inhibitor resembles substrate, offering similar binding sites

Question 2

Vmax in competitive inhibition

Answer 2

Does not change

Question 3

Km in competitive inhibition

Answer 3

Changes, increases

Question 4

Applications of competitive inhibition

Answer 4

Often in pharmaceuticals, eg ethanol to treat methanol poisoning

Question 5

Competitive inhibition at allosteric site

Answer 5

Inhibitor still competes with the ligand for binding, but they have different destinations - both block the other

Question 6

Uncompetitive Inhibition

Anti-competitive

Answer 6

Inhibitor binds to ES complex, preventing EP
Substrate binding may lead to conformational change exposing inhibitor binding site

Question 7

Vmax and uncompetitive inhibition

Answer 7

Decreases
Enzyme removed

Question 8

Km and uncompetitive inhibition

Answer 8

No change
Binding unchanged

Question 9

Noncompetitive inhibition

Answer 9

Inhibitor binds to an allosteric site, deforming the active site
Inhibitor binds equally well to enzyme regardless of binding of the substrate

Question 10

Mixed inhibitor

Answer 10

Noncompetiitive if the inhibitor favours binding to E or ES
Binding prohibits formation of product

Question 11

Vmax in noncompetitivee

Answer 11

Lower
Effectively removes enzyme

Question 12

Km in noncompetitive

Answer 12

Greater