Enzymes Flashcards
Define Cofactor:
Non-protein part of an enzyme needed for activity
Define Coenzyme
Complex organic molecule ususally made from vitamins
Prosthetic group:
Cofacter bound to or tightly associated with the enzyme
Apoenzyme:
Protein component of enzyme
What do enzymes do when they catalyze a reaction?
- Reduce activation energy
- Increase rate of spontaenous reactions
- Increase movement toward equilibria
Define a ribozyme?
A type of enzyme with no protein component.
Catalytic RNA molecules
Examples of co-enzyme
FAD
NAD+
Coenzyme A
Holoenzyme?
Entire enzyme, i.e. both apoenzyme & cofactor
What do these enzyme classes do:
- Oxidoreductases
- Lyases
- Ligases
Oxidoreductases = Transfer electrons Lyases = Form or add groups to double bonds Ligases = Form C-C,C-N,C-S,C-O bonds
What is gibbs free energy?
Basically the available or useful energy generated from a reaction
Spontaneous reactions have -ve deltaG values because they give out energy
To what state is the active site complementary to?
The molecules transition state
In what 3 ways do enzymes reduce activation energy?
- Induced Fit
- Desolvation
- Entropy reduction
Explain induced fit:
Conformational changes in the enzyme force the substrate together or apart
Explain desolvation:
Strong H bonds bind the solvent & subsstrate together
The enzyme replaces these with weaker substrate-enzyme bonds
Explain entropy reduction:
Enzymes force the substrate into the correct orientation, this way theyre interaction isnt just down to chance
