Ch. 18 Control of Gene Expression in Bacteria

These flashcards cover key terminology and concepts associated with the control of gene expression in bacteria.

Gene Expression

The process by which information from a gene is used to synthesize a functional gene product, usually a protein.

Negative Control

A regulatory mechanism that suppresses gene expression; involves repressors that inhibit transcription.

Positive Control

A regulatory mechanism that promotes gene expression; involves activators that enhance transcription.

Regulon

A group of genes or operons that are regulated as a unit, often sharing a common regulatory protein.

Inducer

A molecule that initiates gene expression by disabling a repressor.

Corepressor

A molecule that binds to a repressor and increases its ability to inhibit gene expression.

Promoter

A DNA sequence where RNA polymerase binds to initiate transcription.

Constitutive Expression

Continuous expression of a gene regardless of environmental conditions.

Repressible Operon

A type of operon that is usually on and can be turned off when a specific molecule binds to a repressor.

Inducible Operon

A type of operon that is usually off and can be turned on in response to an inducer.

ToxR Regulon

A group of genes in Vibrio cholerae that are involved in producing cholera toxin and are regulated positively.

SOS Response Regulon

A regulon in E. coli involved in DNA repair processes, activated in response to DNA damage.

Catabolite Activator Protein (CAP)

A protein that enhances the transcription of genes involved in the metabolism of specific sugars.