1. Enzymes

2. What Are Enzymes? Most enzymes are Proteins
Act as Catalyst to accelerate a reaction
Not permanently changed in the process

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

4. Basic Points about Enzymes
Enzymes are biological catalysts that speed up the chemical reactions of the cell.
Enzymes are proteins.
Enzymatic reactions occur faster and at lower temperatures because enzymes lower the activation energy for that chemical reaction.
Enzymes are never consumed or used up during the reaction. They can do their job over and over again

5.                                                                   
Enzymes are highly specific for just one substrate.  The enzyme has an active site with a unique 3-D shape into which this substrate must fit.
Enzymes catalyze both the forward and the reverse of the same reaction.
Enzymes can be denatured by temperatures and pH levels outside the optimal range for that particular enzyme

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

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

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

10. Active Site
The part of an enzyme that binds to the substrate is the active site
Active Site
Enzyme
Substrate

11. Extreme Temperatures Enzymes have an optimum temperature
This means they do the best at a specific temperature
At too hot or too cold and an enzyme may denature (unfold)

12. pH Different enzymes work better at different pH
If the environment becomes to acidic or too basic the enzyme may denature

13. Substrate Concentration
Enzyme needs enough substrate to do its job
Too little substrate causes the enzyme to be ineffective
Too much substrate no longer affects the reaction rate

14. Two examples of Enzyme Inhibitors
a. Competitive inhibitors: are chemicals that resemble an enzyme’s normal substrate and compete with it for the active site.
Enzyme
Substrate
Competitive inhibitor

15. b. Noncompetitive inhibitors:
Inhibitors that do not enter the active site, but bind to another part of the enzyme causing the enzyme to change its shape, which in turn alters the active site.
Enzyme
Noncompetitive
Inhibitor
Substrate
active site
altered

16. Enzyme Inhibitors
Cyanide inhibits an enzyme with the production of ATP. (death)
Penicillin inhibits an enzyme in bacteria that helps cell walls.
Aspirin inhibits enzymes used to induce pain.