Lactase Enzyme Lab What is lactose n Lactose

Lactase Enzyme Lab

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

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

The Result-n 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.

Symptoms Nausea n Cramps n Bloating n Gas n Diarrhea n

Who is at risk? n It is most likely to occur among adults. n Some racial and ethnic groups are more affected than others. n African Americans n Asian Americans n Hispanic Americans n American Indians n http: //digestive. niddk. nih. gov/ddiseases/pubs/lactoseintolerance/#risk

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

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

Bioreactor

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: n n n Lactase enzyme concentration (. 1%, 2%, 3%) Amount of milk (1 m. L, 2 m. L, 3 m. L, 4 m. L) 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 2 m. L of milk (unless your experimental variable is the amount of milk) and 1 m. L of enzyme.