Enzyme Kinetics Flashcards
What is the shape of the graph plotted of reaction rate against substrate concentration?
How do we estimate Km using this?
Hyperbolic graph and then levels out
Km is the substate concentration at half the Vmax
What is the Michealis - Menton equation regulated by?
What rule must there be for it to work?
Kinetic constants
K-1»>K2
What are 3 assumptions we must have?
- concentration of substate is much larger than that of the enzyme so the amount of substrate bound by an enzyme is always small
- Enzyme substate concentration does not change with time
- Initial velocities must be used
What is the equation for MM?
Initial velocity = Vmax[S] / Km + [S]
When the MM is plotted, what shape is it and what kinetic value does it tend towards?
Hyperbolic and it tends towards Vmax
The lower the Km, the — the affinity?
Higher
What does the Kcat mean?
The turnover number of substrates to products over time
What do competitive inhibitors alter and not alter?
Alter the Km value but not the Vmax
What do non-competitive inhibitors alter?
Vmax
What 2 clinical examples can this help?
Control of angiotensin production
Treatment of heart failure