Enzymes (German) - week 5 Flashcards
What do enzymes do and why are they important to the body
- Enzymes increase the RATE of reaction
- Lower amount of free energy required for rxn to take place
- increase probability of rxn occurrence
What is a cofactor in relation to an enzyme
Inorganic ions (Cu2+, Mg2+, Zn2+)
What is a holoenzyme
Complete catalytically active enzyme with coenzymes and cofactors bound
True or false, Enzymes use ionic bonding to chemically change the structure
FALSE
Covalent bonding
Why is weak bonding important in the transition state?
Weak binding is optimal in the transition state, it releases free energy and drives enzyme catalysis
What is velocity and how can it be affected
Velocity is the primary measure of reaction rate
affected by:
- enzyme
- substrate
- cofactors & coenzymes
- enzyme modifications
- ph
- temp
How is the velocity of the rxn calcualted?
Throgh the michaelis-menten equation,
This equations assumes substrate concentration is below Vmax
What is irreversible inhibition?
Inhibitor covalently bids to enzyme, preventing function and leading to degredation (suicide)
Name the 4 reversible inhibition types
- competitive
- uncompetitive
- mixed
- noncompetitive
Define competitive inhibition
Inhibitor competes with substrate to bind w/ enzyme
-Km moves right, not change in Vmax
Define uncompetitive inhibition
Inhibitor binds to the ES complex, but not the enzyme alone
-Reduces Vmax, Km moves LEFT
Define noncompetitive inhibition
Inhibitor binds the enzyme or ES complex, slows or stopes enzymatic process, substrate binding NOT affected
-Reduces Vmax, no change in Km
Define MIXED inhibition
Inhibitor binds enzyme alone or ES complex, affects substrate binding and enzyme function.
-Reduces Vmax, Km moves right
Km moves right but no changes in Vmax
Competitive inhibition
Reduction in Vmax, NO CHANGE in Km
Noncompetitive Inhibition
