Prokaryotic Regulation

Prokaryotic regulation

Mechanisms that control gene expression and cellular activity in prokaryotes.

Operon

A group of genes under the control of a single promoter, involved in the regulation of gene expression.

Feedback inhibition

A regulatory mechanism where the end product of a pathway inhibits an earlier step, preventing overproduction.

Repressible operon

An operon that is usually active but can be inhibited by the presence of a specific molecule.

TRP operon

A repressible operon that regulates tryptophan synthesis; inhibited when tryptophan is abundant.

Corepressor

A molecule that binds to a repressor, activating it to block transcription.

Inducible operon

An operon that requires an inducer to initiate transcription and is usually inactive.

LAC operon

An inducible operon that regulates the breakdown of lactose; only active when lactose is present.

Negative gene regulation

A regulatory mechanism where the active form of a repressor protein blocks transcription.

Positive gene regulation

A mechanism where a protein binds to the promoter to enhance transcription rates.

cAMP

Cyclic AMP, a signaling molecule that increases when glucose levels are low and activates transcription.

CRP (cAMP receptor protein)

An activator protein that enhances transcription by binding to DNA in the presence of cAMP.

Dual control

Regulation involving both positive and negative control mechanisms over gene expression.