1. Enzymes: “Helper” Protein molecules

2. Chemical reactions of life
Processes of life
building molecules
synthesis
breaking down molecules
digestion + +

3. Nothing works without enzymes!
How important are enzymes?
All chemical reactions in living organisms require enzymes to work.
building molecules
synthesis enzymes
breaking down molecules
digestive enzymes
enzymes speed up reactions
Also known as “biological catalysts”
enzyme +
enzyme
We can’t live without enzymes! +

4. Enzymes A protein catalyst
Enzymes are important proteins found in living things. An enzyme is a protein that changes the rate of a chemical reaction.
They speed up metabolic reactions BY LOWERING ACTIVATION ENERGY.

5. Examples
synthesis
enzyme +
digestion
enzyme +

6. Enzymes are PROTEINS!
Each enzyme is the specific helper to a specific reaction. This is known as specificity.
each enzyme needs to be the right 3-D shape for the job
enzymes are named for the reaction they help:
sucrase breaks down sucrose
proteases breakdown proteins
lipases breakdown lipids
DNA polymerase builds DNA
Oh, I get it!
They end in -ase

7. Enzymes aren’t used up
Enzymes are not changed by the reaction. They are:
used only temporarily
re-used again for the same reaction with other substrates
very little enzyme needed to help in many reactions
substrate
product
active site
enzyme

8. It’s shape that matters!
Lock & Key model
shape of protein allows enzyme & substrate to fit
specific enzyme for each specific reaction

9. It’s shape that matters!
Induced Fit model
The combination of the shape of protein and its coenzyme allows enzyme & substrate to fit

10. Factors that affect enzymes:
Temperature pH
Concentration of enzyme and substrate
Presence of Coenzymes (especially for Induced Fit)

11. Enzyme vocab review Enzyme Substrate Products Active site
helper protein molecule
Substrate
molecule that enzymes work on/bind to
Products
what the enzyme helps produce from the reaction
Active site
part of enzyme that substrate molecule fits into