What would happen to regulation from a promoter under negative control if the region where the regulatory protein binds was deleted? What If the promoter was under positive control? Promoters from Escherichia coli under positive control are not close matches to the promoter consensus sequence for E., coll. Why?
To explain:
What would happen to regulation process from a promoter under negative control if the region where the regulatory protein binds was deleted. What if the promoter was under positive control.
Concept introduction:
The regulation of transcription is effective in negative control, because the cell needs the signal for the presence of enough biosynthetic products for their growth. The transcription is also controlled by both negatively or positively because of the presence of lactose and absence of glucose in the culture medium.
Explanation of Solution
The operonal gene products are produced in high amount when the regulatory protein-binding region of a promoter are deleted under negative control. Because of the repressor protein cannot bind to the promoter region. The operonal gene products are not produced when the regulatory protein-binding region of a promoter are deleted. This is because of the activator which cannot attach itself to the promoter region.
To explain:
Promoters from Escherichia coli under positive control are not close matches to the promoter consensus sequence for E. coli. Why.
Concept introduction:
The regulation of transcription is effective in negative control, because the cell needs the signal for the presence of enough biosynthetic products for their growth. The transcription is also controlled by both negatively or positively because of the presence of lactose and absence of glucose in the culture medium.
Explanation of Solution
The DNA consequences matches closely with the promoter region that leads to the binding of the RNA polymerase to the promoter region and stimulates the transcription without the presence of other factors. Thus, a quite different transcription control is seen in the promoters under positive control.
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Chapter 6 Solutions
BROCK BIOLOGY OF MICRO(LL)W/MOD.MASTER.
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