Correct the underlined portion
Production of recombinant human insulin is possible due to Pseudomonas putida.

Explanation

Recombinant insulin production Insulin is a dimeric protein containing two polypeptides A and B joined by two disulphide bonds. Two approaches have been developed for insulin production keeping in mind that it is synthesised as a single polypeptide later cleaved to yield two units A and B. In the first approach, the insulin gene is isolated from beta `(beta)` cells of the pancreatic islets and purified. It is then cloned in E. coli host. The cloned genes are then expressed in an expression host cell of thesame species. It is synthesised as a single polypeptide. Following its synthesis, it is extracted, purified and enzymatically cleaved into A and B polypeptides. The two polypeptides are next joined by two disulphide bonds to yield mature human insulin. This insulin is identified as recombinant human insulin.
A second approach is to use a yeast host cell for the expression of the cloned insulin genes. This approach has an advantage over E. coli host cell in that, yeast, being a eukaryotic cell, expresses, cleaves and joins two polypeptides correctly. Despite this advantage, most of the human insulin manufacturing biotech companies rely on the use of 5. coli as the cloning and expression host.