Enzyme Kinetics

Question 1

Determining the rate of the reaction and how it changes in response to changes in experimental parameters

Answer 1

Enzyme kinetics

Question 2

What does Km tell us about the enzyme?

Answer 2

Binding affinity

Question 3

What does Vmax say about the enzyme?

Answer 3

Fastest the substrate enzyme reaction will go

Question 4

Describes the limiting rate of an enzyme catalyzed reaction at saturation (at Vmax). Describes the ease and difficulty of catalysis by an enzyme. Turnover number

Answer 4

kcat

Question 5

A great way to compare efficiencies of different enzymes

Answer 5

Kcat/Km

Question 6

Rate constant for E+S to E+P when [S]«< Km

Answer 6

Specificity Constant

Question 7

Enzymes that have reached the diffusion controlled limit are said to have achieved what?

Answer 7

Diffusion controlled limit

Question 8

What is Km equal to

Answer 8

1/2Vmax

Question 9

What is the RDS in the substrate enzyme equation?

Answer 9

k2

Question 10

Steady-state assumption?

Answer 10

That ES or total enzyme substrate complex does not change

Question 11

When is Km = [S]

Answer 11

When v0 is 1/2 of Vmax

Question 12

What does a line-weaver burke plot show?

Answer 12

Shows more accurate enzyme kinetics. Shows slope, y-int, and x-int. All can be used to find specific values

Question 13

Slope of line-weaver burke is equal to what?

Answer 13

Slope = Km/Vmax

Question 14

Y-int of line-weaver burke is equal to what?

Answer 14

1/Vmax

Question 15

X-int of a line-weaver burke plot is equal to what?

Answer 15

-1/Km

Question 16

Kcat/Km has an upper limit due to diffusion. Enzymes that reach this limit are called what? What is the limit?

Answer 16

They are called catalytic perfection. The limit is 10^8/ Ms through 10^9/ Ms