1. Lactase Enzyme Lab

2. What is lactose?
Lactose is a sugar that is found in milk and many dairy products.

3. Causes of Lactose Intolerance
Small intestine does not make enough of the enzyme LACTASE which is responsible for breaking down lactose into simple sugars (glucose & galactose)

4. The Result--
Lactose is not absorbed in the small intestine, but is instead fermented by bacteria in the large intestine producing large volumes of carbon dioxide gas.

5. Symptoms
Nausea
Cramps
Bloating
Gas
Diarrhea

6. Who is at risk? It is most likely to occur among adults.
Some racial and ethnic groups are more affected than others.
African Americans
Asian Americans
Hispanic Americans
American Indians

7. Although taking the over-the-counter enzyme LACTASE can decrease symptoms—it will not get rid of them all together!

8. How does the biotech industry produce lactase?
Lactase is obtained from a type of yeast called Kluveromcyes lactis.
The gene that codes for lactase is isolated from the yeast and amplified (through what process?).
Once the gene is amplified it is inserted back into the yeast cells so the cells produce that protein.
The yeast cells are then placed in bioreactors where they reproduce (in very large quantities).

9. Bioreactor

11. Tuesday’s Lab (not today!)
After completing part 1 of the lab, you will be designing your own lab. You will be able to test your choice of the following variables:
Lactase enzyme concentration (.1%, 1%, 2%, 3%)
Amount of milk (1mL, 2 mL, 3 mL, 4mL)
Temperature (4, 25, 37, or 100° C)
You will either use skim milk or whole milk for your experiment.
In all experiments you will use 2mL of milk (unless your experimental variable is the amount of milk) and 1mL of enzyme.