Q20.1-3CC. What are some potential difficul... [FREE SOLUTION]

Chapter 20: Q20.1-3CC. (page 421)

What are some potential difficulties in using plasmid vectors and bacterial host cells to produce large quantities of proteins from cloned eukaryotic genes?

Short Answer

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There are many difficulties in cloning eukaryotic genes in plasmid vectors and bacterial host cells. It is challenging to incorporate sizeable eukaryotic genes into the bacterial plasmid.

On the other hand, eukaryotic and prokaryotic cells have different gene expression systems. Moreover, bacterial cells lack RNA processing and post-translational modification required to achieve a functional eukaryotic protein.

Step by step solution

Plasmid vectors cannot clone large eukaryotic genes

Plasmid vectors are small in size. They can clone a gene of 15kb or less than that. However, eukaryotic genes are significant in size. As a result, it becomes difficult to incorporate the large eukaryotic genes into the small plasmid vector.

Difference of gene expression in prokaryotic and eukaryotic cells

The gene expression machinery and the signals that regulate the gene expression are different in these cells. For this reason, to clone eukaryotic genes, promoters are required to be added to the vectors to achieve the expression of the eukaryotic gene.

Bacterial cells lack RNA processing and post-translational modifications

Eukaryotic genes contain introns. However, bacterial cells lack RNA processing, such as RNA splicing. RNA splicing is involved in removing introns from the RNA transcript to yield mature mRNA that can undergo translation.

Bacterial cells also lack the enzymes required for post-translational modification of proteins, such as phosphorylation, acetylation, methylation, and many more. All these modifications are necessary to synthesize a functional eukaryotic protein.