1. Biochemistry:
Enzymes

2. Is anyone Lactose intolerant?
What is that?

3. Enzymes A specialized type of protein
Function in our body: acts like a catalyst = substance that speeds up the rate of a chemical reaction but it is not used up in the reaction.

4. Enzymes
Enzyme(s) reduce the activation energy = amount of energy needed to begin a reaction
Usually end is “–ase”.
Coenzymes = an organic molecule associated with the enzyme to help in the reaction.

5. Progress of the reaction Free energy of activation
Enzymes
Free
Energy
Progress of the reaction
Reactants
Products
Free energy of activation

6. Enzymes Need an active site on the enzyme
Active site = attracts and hold only specific molecules called substrates.
“Lock and key” system- one “key” will fit “lock”; perfect fit
Induced Fit – “lock” will mold around the “Key” if fit is close enough

7. Enzymes
Therefore, enzymes enable molecules called substrates to undergo a chemical change to form new substances called products.

8. Enzymes
Active Site

9. Example of the hydrolysis of sucrose using the enzyme (sucrase)

10. Enzyme Inhibitors
Competitive Inhibitors = a substances that reduces the activity of an enzyme by entering the active site in place of the substrate whose structure is very similar.

11. Enzyme Inhibitors 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.

12. Enzymes
Could not survive without enzymes! (almost all chemical reactions in cells require an enzyme)
Speeds up reactions in:
Digestion of food
Synthesis of molecules
Storage and release of energy

13. Enzymes Enzymes are named for the compounds they work on.
You drop the current compound ending and replace it with –ase.

14. Enzymes For example: Lactose’s enzyme is lactase
Maltose’s enzyme is maltase
Sucrose’s enzyme is sucrase
Amylase (in your saliva) is the enzyme for starch (amylose)

15. Enzymes 2 Factors that Affect Enzymes:
Temperature – Too high temperatures will denature (change the shape of) the active site of the enzyme, causing the enzyme to not work properly.
pH – every enzyme has an optimum pH in which they will work. Altering the pH will cause the enzyme to not work properly.

16. Examples Cat box example pH (most like 6 - 8 pH near neutral)
Urea + urease  ammonia + carbon dioxide
Clean litter in cooler temps = less smell due to slower rate of reaction
pH (most like pH near neutral)
Lemon Juice on apple
Polyphenol oxidase (PPO) is the enzyme that reacts with oxygen to turn the apple brown

17. How Does our Body get Energy from the Breaking Down of Molecules?
Energy is released when a chemical bond is broken.

18. Enzymes Analysis of Enzyme actions
Draw a conclusion based on each graph below!

24. Dehydration synthesis or hydrolysis?