Question

In one of the techniques of recombinant insulin production the genes $\alpha$ and $\beta$ polypeptides were inserted into the plasmid by the side of
(a) Antibiotic resistance gene
(b) Lac z promoter gene
(c) $\beta$ galactosidase gene
(d) Ori

Answer 1

The recombinant insulin can be produced by the insertion of the genes for $\alpha$ and $\beta$ polypeptides and integrating them with the bacterial plasmid DNA. These genes are inserted by the side of that gene of the plasmid that regulates gene expression.
Complete Step by Step Answer:
The recombinant insulin is produced as an application of biotechnology, by the insertion of the genes for $\alpha$ and $\beta$ polypeptides into the bacterial plasmid by the side of the beta- galactosidase gene. It is the gene that regulates the gene expression in a cell.
With the integration of the gene with the plasmid genome, the gene expresses itself and leads to the production of recombinant insulin. This recombinant human insulin is also called as Humulin.
The polypeptides thus obtained are then purified and disulphide bonds are then added to obtain the final form of insulin.
- Since the plasmid DNA is also inherited in the offspring, the insulin gene is thus replicated in the next generations of the bacteria. So, it may not be necessary to carry out the recombination procedure to include the gene in the bacterial DNA.
- This recombinant insulin production is usually carried out with the help of bacteria like E. coli which have low duplication time, and hence more insulin can be produced in less time.
So, the correct answer is, ‘(c) $\beta$ galactosidase gene’.

Note: Earlier to recombinant human insulin, insulin from the pancreas of cows and pigs was extracted and used for diabetic patients which were less potent and also induced allergic reactions in many patients.