Enzme II

Question 1

_______are especially potent inhibitors

Answer 1

Transition-state

Question 2

Simplest Model Mechanism

Answer 2

Question 3

Irreversible Inhibition

Answer 3

1. Permanently inactivate the enzyme
2. Has no effect on Km
3. Vmax decreases
4. Enzyme is covalently modified

Question 4

Noncompetitive inhibition

Answer 4

1. Km does not change
2. Vmax decreases
3. Binds to enzyme and ES complex

Question 5

Know Lineweaver Burke Plot equation

Answer 5

1/v₀ = (k_m/v_max)(1/[S])+(1/V_max)

Question 6

Example of a competitive inhibitor

Answer 6

Sulfanilamide is competitive inhibitor of p-aminobenzoic acid (folic acid)

Question 7

If Km goes up, the affinity goes ____

Answer 7

Down

Question 8

Competitive Inhibitor

Answer 8

1. Km goes up
2. Vmax does not change
3. Binds to active site of enzyme

Question 9

Examples of Irreversible Inhibition

Answer 9

Diisopropylphosphofluoridate permanently deactivates serine proteases

Question 10

Uncompetitive inhibition

Answer 10

a. Binds to the ES complex
b. Decreases Km and Vmax

Question 11

Noncompetitive Inhibition

Answer 11

AMP is a noncompetitive inhibition of fructose 1,6-bisphosphate

Question 12

Types of Inhibition

Answer 12

1. Competitive
2. Non Competitive
3. Uncompetitive
4. Irreversible

Question 13

At the steady state the substrate has dissociated into _____.

Answer 13

Product

Question 14

Michaelis-Menton equation

Answer 14

V= (Vmas[S])/Km+[S]

Question 15

Draw Michaelis Constant Graph

Answer 15

Question 16

What is k_cat?

Answer 16

How many substrate molecules can one enzyme molecule convert per second

Question 17

Equations for Km

Answer 17

1. Km= (k2+k3)/k1
2. Km= ½ Vmax

Question 18

______is a suicide inhibitor

Answer 18

Penicillin

Question 19

Draw Lineweaver Burke Plot

Answer 19

Question 20

Vmas equation

Answer 20

Vmas= k3[Et]

Question 21

Draw Substrate Saturation Curve

Answer 21

Question 22

What is K_m?

Answer 22

Measure of substrate’s affinity for enzyme

Question 23

________inhibitor dissociates very slowly because it has become tightly bound to the enzyme, either covalently or noncovalently.

Answer 23

Irreversible

Question 24

Example of Uncompetitive inhibition

Answer 24

Phenylalanine is an uncompetitive inhibitor of alkaline phosphatase