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You have created a strain of E. coli in which the 5’ leader sequence of the...

You have created a strain of E. coli in which the 5’ leader sequence of the trp operon has been mutated to replace all of the tryptophan codons with arginine codons. How will this affect the expression of the trp operon and the arginine operon?

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Answer #1

ans) Please refer the diagram of operon given in the image at the end.

1.Tryptophan operon can be switched off either by the repressor or the attenuator structure present in the leader sequence when there is high level of tryptophan.

2. In the above experiment the 5' leader sequence is mutated which lead to the replaement of all trp codons with arginine codons, so in case of low tryptophan the trp operon will be switched on but will lead to the production of Arginine.

3. However Arginine operon wll be switched off because of presence of high levels of arginine produced by the mutated trp operon.

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