Prokaryote Gene Expression

A set of flashcards designed to cover key vocabulary and concepts related to prokaryote gene expression based on the provided lecture notes.

Differential Expression of Genes

The regulation of genes to ensure that not all genes are expressed at all times, allowing for energy conservation and cell specialization.

Feedback Inhibition

A regulatory mechanism where the end product of a metabolic pathway inhibits an earlier step to prevent overproduction of the end product.

Bacterial Operon

A cluster of genes under the control of a single promoter, which can be regulated collectively.

trp Operon

A repressible operon that is normally on but can be turned off by high levels of tryptophan.

lac Operon

An inducible operon that is normally off but can be turned on in the presence of lactose.

Repressor Protein

A protein that binds to the operator region of an operon to inhibit transcription.

Corepressor

A small molecule that binds to a repressor protein to activate it, leading to repression of gene transcription.

Activator Protein (CAP)

A protein that increases gene transcription by binding to a specific site on the DNA.

Inducible Operon

An operon that is usually off but can be turned on in response to an inducer.

Repressible Operon

An operon that is usually on but can be turned off when a corepressor is present.

Negative Gene Regulation

Regulation of gene expression that involves repression of transcription by repressor proteins.

Positive Gene Regulation

Regulation of gene expression that enhances transcription initiation through the use of activator proteins.

cAMP

A molecule that serves as a secondary messenger in cellular signaling and is involved in the regulation of the lac operon.

RNA Polymerase

An enzyme that synthesizes RNA from a DNA template during transcription.

Operon Model

A model that describes how genes are regulated in prokaryotes, including components like the promoter, operator, and structural genes.

Tryptophan (Trp)

An amino acid used in protein synthesis that also functions as a corepressor in the trp operon.

Allolactose

An inducer for the lac operon that inactivates the repressor, allowing transcription.

Resource Rationing

The practice of using cellular resources efficiently to survive in changing environmental conditions.

Inducer

A molecule that initiates gene expression by inactivating the repressor for an operon.