Question

Human insulin is being commercially produced from a transgenic species of?

A) Escherichia coli
B) Mycobacterium
C) Rhizobium
D) Saccharomyces

Answer 1

Hint: The bacteria which have an origin of replication for replication, a selectable marker to distinguish and cloning sites to link the alien DNA, for commonly used restriction enzymes the vector needs to have very few, preferably single, recognition sites.
Complete step-by-step answer:
Insulin used for diabetes was earlier extracted from the pancreas of slaughtered cattle and pigs. Insulin from an animal source, though caused some patients to develop an allergy or other types of reactions to the foreign chains. So, Genetically engineered E.coli produce human insulin.
By the use of recombinant DNA technology or genetic engineering, insulin-producing genes from human beings have been transferred into E.coli.
Bacteria produced insulin called 'humulin' (brand name of insulin )for clinical use.
This type of insulin was produced commercially by an American pharmaceutical company Eli Lily on 5th July 1983. And E.coli is such bacteria that fulfils all the requirements need for a cloning vector.
Rhizobium is a nitrogen-fixing bacteria and is a soil bacteria that help in nitrogen fixation in leguminous plants. It attaches to the roots of a leguminous plant and produces nodules. These nodules fix atmospheric nitrogen and convert it into ammonia that can be used by the plant for growth.
Saccharomyces is a fungus called baker’s yeast and plays a key role in food fermentations and other industrial processes.
Mycobacterium is disease causing specie of bacteria like tuberculosis and leprosy in humans.

Therefore the correct answer is Option A.
Note Eli lily an American company prepared two DNA sequences corresponding to A and B, chains of human insulin and introduced them to plasmids of E.coli to produce insulin chains. Chains A and B were produced separately and extracted then chain A and chain B were combined by creating disulfide bonds to form human insulin.