Enzymes PG-73

Question 1

Why is it better to genetically modify the yeast to make chymosin instead of retrieving it from a calves’ stomach?

Answer 1

It is better because it is cheaper and easier to produce very large amounts of completely pure chymosin. Also easier to make different cheeses, including those for vegetarians.

Question 2

What is recombinant DNA technology?

Answer 2

This is the act of ‘combining’ DNA in a new way, such as the creation of bacteria that contained the human gene for making insulin.

Question 3

Describe the process for creating the insulin combined bacteria.

Answer 3

DNA from a human cell is cut into pieces using restriction enzymes. Make staggered cuts across the DNA and leave a few unpaired bases called the sticky ends. The bacteria cells have small circles of DNA called plasmids which are also cut open with the restriction enzymes and leave the sticky ends. Them these two are brought together and the sticky bases find eachother and pair up. This new insulin plasmid creation is inserted back into the bacteria which can be grown in big fermenters to make an abundance of human insulin.

Question 4

Nowadays, what is chymosin made from?

Answer 4

Genetically modified yeast.