Gene Regulation in Bacteria

These flashcards cover key concepts related to the regulation of gene expression in bacteria, including mechanisms of transcriptional and translational regulation.

What is gene regulation?

The ability of cells to increase or decrease the expression of specific genes based on environmental conditions.

What are constitutive genes?

Genes that are constantly expressed and maintain constant levels of expression.

Why is gene regulation beneficial?

It allows proteins to be produced only when needed, optimizing resource use.

What processes in cells does gene regulation impact?

Metabolism, response to environmental stress, and cell division.

What are the two main types of regulatory proteins in transcriptional regulation?

Repressors, which inhibit transcription, and activators, which enhance transcription.

Describe negative control in gene regulation.

Transcriptional regulation by repressor proteins that inhibit transcription.

What do inducers do in gene regulation?

Inducers increase transcription by binding to activator proteins or preventing repressors from binding to DNA.

What is a corepressor?

A small effector molecule that enhances the binding of a repressor protein to DNA, inhibiting transcription.

What is the lac operon?

A regulatory unit consisting of structural genes and regulatory sequences that control lactose metabolism in E. coli.

What role does allolactose play in the lac operon?

Allolactose is an inducer that binds to the lac repressor, inactivating it and allowing transcription of the lac operon.

How does catabolite repression function in the lac operon?

E. coli preferentially utilizes glucose over lactose, inhibiting the expression of the lac operon until glucose is depleted.

What is attenuation in gene regulation?

A regulatory mechanism where transcription is prematurely terminated, especially in response to high levels of tryptophan.

How do riboswitches regulate gene expression?

By changing conformation in response to a small molecule, which can either promote or inhibit translation.

What is feedback inhibition?

A regulatory mechanism where the end product of a metabolic pathway inhibits an early-stage enzyme in that pathway.

What covalent modifications can affect protein function?

Phosphorylation, acetylation, methylation, and proteolytic processing.