MB - Enzyme Kinetics

Question 1

How can you measure the change of [S] or [P] over time?

Answer 1

Use of a Spectrophotometer
- Measures absorbance change over time

Question 2

What does ‘V’ stand for and what are its units?

Answer 2

Reaction Velocity - mol/min

Question 3

What is Vmax determined by?

Answer 3

Number of enzyme molecules not number of substrate molecules

Question 4

What is Kd?

Answer 4

Dissociation constant- affinity for substrate (Small Kd = high affinity)

Question 5

What is Km?

Answer 5

Michaelis Constant
(k-1 + kcat)/K1

Question 6

What is the Michaelis-Menten equation?

Answer 6

V=(Vmax x [S])/(Km + [S])

Question 7

What are isoenzymes?

Answer 7

Different enzymes, Same substrate

Question 8

What are the 3 main ways enzymes are compared?

Answer 8

1. Turnover number
2. Efficiency
3. Potency

Question 9

What is turnover number?

Answer 9

Number of reactions per second

Question 10

What is enzyme efficiency?

Answer 10

Catalytic speed vs Binding affinity

Question 11

What is enzyme potency ?

Answer 11

How many times faster reaction is with enzyme