Which part of the TRP operon includes the genes that are expressed?

The structural genes are the portions of the TRP operon that encode the proteins necessary for the synthesis of tryptophan. In prokaryotic operons, such as the TRP operon found in Escherichia coli, structural genes are arranged in a sequence and transcribed together as a single mRNA molecule, which can then be translated into multiple polypeptides. This organization allows for coordinated regulation and expression of genes involved in the same metabolic pathway.

In the case of the TRP operon, there are several structural genes that contribute to the biosynthesis of tryptophan, specifically trpE, trpD, trpC, trpB, and trpA. These genes are expressed when the regulatory elements of the operon allow RNA polymerase to initiate transcription, ultimately leading to the production of enzymes that facilitate the biosynthesis of tryptophan from simpler precursors.

Other parts of the operon, such as the promoter and operator, play crucial roles in the regulation of gene expression but do not consist of the genes themselves. The promoter is the region where RNA polymerase binds to initiate transcription, while the operator is the segment that can bind repressor proteins to inhibit transcription. The leader