Enzyme kinetics Flashcards
What are the 3 characteristics of enzyme catalysts?
- High activity
- Specificity
- High efficiency
What do catalysts lower?
The activation energy
How do we measure the effectiveness of enzymes? (2)
Measure the product formed
Measure the substrate used
What is an enzyme unit?
1 unit of enzyme activity (U) = amount of enzyme which transforms substrate into product
How does temperate effect enzymes?
Increase until certain point then denaturing
What enzyme can work at high temperatures?
Taq polymerase
How does pH effect enzymes?
pH can cause a change in shape of enzyme
How does substrate concentration influence enzymes?
Increases the rate
What is Km?
Michaelis constant Km - concentration of S when V0 = Vmax/2
What is Vmax?
Maximum velocity Vmax - value of V0 when [S] is high - active site saturated
What is the Michaelis mention equation?
Vo = Vmax[S] / Km+[S]
Why is Km important?
Km = the substrate conc. at which the reaction rate is half maximal velocity
High Km = weak substrate binding
Low Km = strong substrate binding
What are the units for Km?
Doesn’t have any! Syk
What is Kcat?
It is the turnover constant of the enzyme - molecules of substrate transformed per unit time
What is the Kcat equation?
Kcat = Vmax / [Et]
