This chapter contains a lengthy discussion of the trp operon involved in regulating the synthesis of tryptophan. In the case of E. coli, the bacterium may need to synthesize tryptophan, or its host, a human, may supply all the tryptophan it needs. Why do both bacteria and humans need tryptophan?
It is important in inducing sleep.
It is an important constituent of cell walls in both humans and bacteria.
Tryptophan induces the lac operon.
It is an important enzyme in the glycolysis pathway.
It is one of the 20 amino acids used by all organisms to synthesize proteins.