Question

What effect will deletion of the trpL region of the trp operon have on the rates of synthesis of the enzymes encoded by the five genes in the trp operon in E. coli cells growing in the presence of tryptophan? Explain your answer.

Answer 1

trrpL is the trp operon leader peptide. This leader peptide has an important role in maintaining or regulating the biosynthesis of tryptophan. In the trpL region the RNA polymerase produces the leader transcript which is translated into the leader peptide - an important part for the tryptophan molecule. Also the trpL region acts as a pause-site for RNA polymerase to make sure that transcription and translation are going on simultaneously. Just after the trpL region is the attenuator sequence. Thus deletion of the trpL region of the trp operon will result to reduction of rates of synthesis of the enzymes encoded by the five genes in the trp operon in E. coli cells and finally stop or attenuate the process in the presence of tryptophan.