1. Enzymes

2. What Are Enzymes?
Most enzymes are Proteins (tertiary and quaternary structures)
Act as Catalyst to accelerates a reaction
Not permanently changed in the process

3. Enzymes Are specific for what they will catalyze Are Reusable
End in –ase
-Sucrase
-Lactase
-Maltase

4. Enzymes work by weakening bonds which lowers activation energy
How do enzymes Work?
Enzymes work by weakening bonds which lowers activation energy

5. Enzymes Without Enzyme With Enzyme Free Energy
Progress of the reaction
Reactants
Products
Free energy of activation

6. Enzyme-Substrate Complex
The substance (reactant) an enzyme acts on is the substrate
Enzyme
Joins
Substrate

7. Active Site
A restricted region of an enzyme molecule which binds to the substrate.
Active Site
Enzyme
Substrate

8. Induced Fit A change in the shape of an enzyme’s active site
Induced by the substrate

9. What Affects Enzyme Activity?
Three factors:
1. Environmental Conditions
2. Cofactors and Coenzymes
3. Enzyme Inhibitors

10. 1. Environmental Conditions
Extreme Temperatures are the most dangerous
high temps may denature (unfold) the enzyme.
Amylase – works best at body temperature
98.60C or 370C
Why is it bad to have a high temperature?

11. pH (most like 6 - 8 pH near neutral)
Amylase likes a neutral to 8 pH
Hence, the reason that the pH must change from the acidic environment in the stomach to the neutral environment in the small intestines.
Ionic concentration (salt ions)

12. 2. Cofactors and Coenzymes
Inorganic substances (zinc, iron) and vitamins (respectively) are sometimes need for proper enzymatic activity.
Example:
Iron must be present in the quaternary structure - hemoglobin in order for it to pick up
oxygen.

13. Enzyme Inhibitors Inhibitor
Inhibitors do exactly what their names suggests: They inhibit the enzyme from working.
Chemical binds at the active site OR
Chemical binds to another part of the enzyme forcing the active site to change shape…substrate cant bind.
Enzyme
Inhibitor
Substrate
Noncompetitive
Inhibitor