Concept explainers
Attenuation affects anabolic pathways, whereas repression affects either anabolic or catabolic pathways. Provide an explanation for this.
The bacterial cells can also regulate the process of transcription termination in addition to regulating the transcription initiation. In such type of regulation, the transcription is initiated but stopped prematurely depending on the needs of the organisms and their environmental conditions. Attenuation is an example of this kind of regulation. Repression refers to the “turning off” of genes with the help of a repressor factor. This factor prevents the binding of RNA polymerase to its promoter region or prevents it from reading the downstream DNA thereby prevents the mRNA synthesis.
Explanation of Solution
Attenuation is a kind of regulatory mechanism. It involves the interaction between the transcriptional and translational machinery. This interaction specifically occurs in RNA polymerase and ribosomes. In the cell, this mechanism senses the specific amino acid levels or other metabolites. Thus, it is found to be limited in regulating anabolic operons for the biosynthesis of amino acids and other metabolites.
In order to govern the transcription process, the repressor proteins are used in repression. It can be used either to allow the transcription in the presence of an inducer or to block the transcription in the presence of co-repressor. It is found to be a more flexible and general process of gene regulation. Thus, it affects both anabolic and catabolic pathways.
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Chapter 14 Solutions
Prescott's Microbiology
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