Protein biochemistry and enzymology

Question 1

What is the Michealis-Menten equation?

Answer 1

v = Vmax [s] / Km + [s]

Question 2

What is the y-intercept on a lineweaver-Burke plot?

Answer 2

1/Vmax

Question 3

What is the x-intercept on a lineweaver-Burke plot?

Answer 3

-1/Km

Question 4

Define Km

Answer 4

Substrate concentration at which the rate is half of the Vmax - Michaelis constant

Question 5

Define Kcat

Answer 5

Turnover number - measure of how many substrate molecules an enzyme can convert into product per second when the enzyme is fully saturated with substrate

Question 6

What is the equation to find Kcat?

Answer 6

Kcat = Vmax / [Etotal]

Question 7

What happens to the Vmax and substrate concentration during competitive inhibition?

Answer 7

Vmax stays the same, and substrate concentration required to produce the Km is increased

Question 8

If inhibition is strong, is the Ki high or low?

Answer 8

Low

Question 9

What is Ki and what does it measure?

Answer 9

Inhibition constant - measures how strongly an inhibitor binds to an enzyme. Represents the concentration of inhibitor needed to reduce the enzyme activity by half