Question

How would transcription of the E. coli trp operon be affected by changing the two Trp codons in the leader peptide gene to His codons?

Answer 1

Answer:

The attenuation system would respond more to histidine (His) than to tryptophan (Trp) levels

Explanation:

In genetics, the attenuation system refers to the process of control which is responsible for triggering premature termination of transcription in bacterial operons. In bacteria, the process of attenuation is characterized by the presence of an attenuator, which is a stop signal sequence found in the leader mRNA. The tryptophan (trp) operon, which is a cluster of genes responsible to encode the components required during the production of tryptophan, is controlled by the attenuation system. When there is a high tryptophan level, the ribosomes are able to translate an attenuator sequence, thereby resulting in termination of transcription. The attenuation system also controls the synthesis of other amino acids including histidine (His), phenylalanine (Phe) and threonine (Thr).