Lecture 19 Flashcards
What is Vmax
measure of the catalytic effectiveness of the enzyme
higher the Vmax, more product formed per minute
What is Km (Michaelis constant)?
concentration of a substrate necessary to produce half of Vmax
At high concentration of substrate, what is the order of reaction and why?
Zero order, because reaction is independent of substrate concentration ([s]»>Km)
At low concentration of substrate, what is the order of reaction and why?
First order, because reaction is dependent on substrate concentration. ([s]<
What does it mean if there is increase in Km?
The enzyme reflects a low affinity of enzyme for the substrate.
How is Km related to affinity of enzyme for substrate?
Smaller the Km, larger the affinity of enzyme.
Michaelis and Menten equation
V = [Vmax * [S]] / Km+[S]
Lineweaver and Burk equation
1/V = [Km + [S]] / Vmax * [S]
What does y-intercept mean in Linewevaer and Burk graph?
1/Vmax
What does X-intercept mean in Linewevaer and Burk graph?
-1/Km
2 types of inhibition
irreversible and reversible
What bond is formed for irreversible inhibition?
covalent bond
3 types of reversible inhibition
Competitive, noncompetitive, uncompetitive
How can competitive inhibition overcome?
increase substrate concentration
Example of competitive inhibitor
Statin (Lovastatin)