Tryptophan (trp) operon

Definition

The tryptophan (trp) operon is a group of genes in prokaryotes that are used to synthesize the amino acid tryptophan. It is regulated by a repressor protein that inhibits gene expression when tryptophan levels are sufficient.

5 Must Know Facts For Your Next Test

1. The trp operon consists of five structural genes necessary for tryptophan synthesis.
2. It operates using a negative feedback mechanism where high levels of tryptophan activate a repressor protein.
3. The trp repressor binds to the operator region, blocking RNA polymerase from transcribing the genes.
4. In the absence of tryptophan, the repressor is inactive, allowing gene transcription.
5. Attenuation is another regulatory mechanism where transcription is prematurely terminated if tryptophan levels are high.

Related terms

Lac Operon: A set of genes involved in lactose metabolism and regulated by lactose availability.

Repressible Operon: A type of operon that can be inhibited by a specific molecule binding to its regulatory protein.

Attenuation: A regulatory mechanism where translation influences transcription termination based on metabolite concentration.