a.
Mutagenesis:
The process of producing mutagens is called mutagenesis. Mutagens are chemical, physical or biological agents that increase the mutation rate. Mutagens can alter DNA in many different ways, but such alterations are not mutations unless they can be inherited.
a.
Explanation of Solution
One of the another utilized approach is called Mutagenesis. This approach uses chemical ultraviolet light and transposon mutagenesis to increase the yield of the product. The benefits are that, if there is a useful mutation, there will be high product yield.
Unfortunately, mutagenesis is not extremely accurate and many different mutants would have to be screened before the one of interest is found.
Therefore, mutagenesis process can be used for the alteration of DNA produce metabolites.
b.
Heterologous gene expression
When genes from one organism are cloned into another it is called Heterologous gene expression.
b.
Explanation of Solution
In the Heterologous gene expression, after cloning then it is transcribed and translated into protein. For example heterologous gene expression is the cloning and expression of the human insulin genes in E. coli.
Heterologous gene expression allows specific proteins and peptides to be produced without contamination by other products which could be synthesized in the original organism. This approach may reduce the time and cost of a product being recovered and purified.
Therefore, Heterologous gene expression provides specific proteins and peptides to be produced without contamination by other products.
c.
Cloning of gene from one to another one is called as Heterologous gene expression.
c.
Explanation of Solution
The last method is utilizing heterologous gene expression by using a bacterial promoter that will drive constitutive expression of the product. As the productivity will increase exponentially by using this method.
However, just as in the case of heterologous gene expression, transfection and transduction are sometimes very difficult to achieve.
Also, by utilizing the bacterial promoter, there may be some problems in production of the needed metabolite. It’s because sometime, there are negative feedback loops that organisms utilize.
Therefore, heterologous expression of the genes responsible for producing this product in a bacterial host but using a bacterial promoter that will drive constitutive expression of the product.
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Chapter 42 Solutions
Prescott's Microbiology
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