Lecture 23 pt 3 Bacterial Gene Regulation - TRP Operon

Vocabulary flashcards for bacterial gene regulation focusing on the TRP operon, repressors, and allosteric control.

Operon

A set of genes that are clustered together and required to make the enzymes necessary for a specific metabolic pathway (in this case, tryptophan synthesis).

Repressible Operon

A type of operon where its default state is 'on' (transcribed), but it can be switched off when the end product (e.g., tryptophan) is readily available.

Repressor Protein

A regulatory protein that can bind to the operator region of an operon and prevent RNA polymerase from transcribing the genes.

Repressor Gene (trpR)

A gene that codes for a repressor protein. It is transcribed and translated continuously, resulting in a constant level of repressor protein in the cell.

Constitutively

The state where a gene is continuously transcribed and its protein product is constantly produced.

Co-repressor

A small molecule (e.g., tryptophan) that binds to a repressor protein, causing a conformational change that allows the repressor to bind to the operator and inhibit transcription.

Allosteric Regulation/Control

Regulation where the binding of a molecule to a protein affects the protein's function at a different site, causing a conformational change.