1. Enzymes

2. Enzymes are Proteins
Made at ribosome
Monomer: AA
Peptide bonds

3. Enzymes act as catalysts
Speed up rxns by lowering activation energy
Activation energy = starting energy

4. Enzymes are reusable - do not get used up Enzymes do not change
Enzymes end in –ase
EX: Lactase

5. Substrates bind to enzymes at the active site
Substrate – what the enzyme acts on
Active site – where the substrate binds/attaches to

6. 2 ways enzyme and substrate bind
Lock & Key – fit perfectly together

7. 2. Induced Fit – enzyme changes
shape to fit the substrate

8. Inhibitor (2 types)
Competitive – blocks substrate
Non-competitive – changes enzyme shape by binding elsewhere

9. Factors affecting inhibitor activity
Denature – decreases function by
pH or , temperature or
NOT AT OPTIMUM
Substrate [ ] – once enzymes are saturated, activity does not increase
Enzyme [ ] – when enzymes are increased to act on substrates

10. Questions What are enzymes? How do enzymes affect rate of reaction?
How does a catalyst speed up a reaction?
What is polymerase?
Can an enzyme be reused?
What would happen to a reaction if the enzyme is removed?
If an inhibitor binds to an enzyme on the active site, what type of inhibitor is it?
If the substrate binds to the enzyme perfectly at the active site, what type of bond is it?
If an inhibitor binds to an enzyme on a different site, what type of inhibitor is it?
If the enzyme has to change its shape to fit the substrate, what type of bond is it?
If substrate [ ] is saturated, can the enzyme activity increase?
If substrate [ ] is saturated, what needs to be added in order for enzyme activity to increase?
If enzyme [ ] is saturated, what needs to be added in order for the activity to increase?