Chapter 7

A comprehensive set of vocabulary flashcards based on the concepts from the Microbial Regulatory Systems lecture notes, designed to aid in exam preparation.

DNA-Binding Proteins

Proteins that bind to specific DNA sequences to regulate gene expression.

Operon

A group of genes transcribed as a single mRNA molecule under the control of a promoter.

Promoter Region

The region of DNA where RNA polymerase binds to initiate transcription.

Transcription Factors

Proteins that control the rate of transcription of a gene by binding to specific DNA sequences.

Activator Protein

A type of transcription factor that increases the transcription of a gene.

Repressor Protein

A type of transcription factor that inhibits gene expression by binding to an operator.

Effector

Small molecules that influence the activity of transcription factors.

Homodimeric Proteins

Proteins formed by two identical polypeptides that can bind to DNA.

Inverted Repeats

Nucleotide sequences that are followed downstream by their reverse complement, often binding sites for regulatory proteins.

Allosteric Proteins

Proteins whose activity is regulated by the binding of effector molecules, resulting in conformational changes.

Corepressor

A molecule that binds to a repressor protein, allowing it to bind to the operator and inhibit transcription.

Inducer

A small molecule that binds to a repressor protein and prevents it from binding to DNA, allowing transcription to occur.

Basal Transcription

The low level of transcription that occurs even when a repressor is active.

Positive Control

A regulatory mechanism where a protein helps promote transcription.

Negative Control

A regulatory mechanism where a protein inhibits transcription.

Signal Transduction

The process by which external signals are converted to cellular responses.

Quorum Sensing

A regulatory mechanism by which bacteria assess their population density through signaling molecules.

Chemotaxis

Movement of organisms in response to chemical stimuli.

Two-Component Regulatory Systems

Signal transduction systems that involve a sensor kinase and a response regulator.

Feedback Inhibition

A regulatory mechanism where the end product of a pathway inhibits an enzyme involved in its synthesis.

Riboswitches

Regulatory segments of mRNA that bind small molecules, resulting in conformational changes that affect gene expression.

Attenuation

Transcriptional control mechanism where premature termination of mRNA synthesis occurs.

Cyclic AMP (cAMP)

A signaling molecule that activates certain proteins, including the cyclic AMP receptor protein.

Cyclic AMP Receptor Protein (CRP)

An enhancer protein that binds to cAMP and activates gene transcription.

Regulon

A group of operons or genes controlled by the same regulatory protein.

Sigmoidal Growth Curve

Represents the growth of organisms, typically showing exponential growth phases.

Heat Shock Proteins

Proteins that help refold denatured proteins and protect cells from stress.

Alternative Sigma Factors

Proteins that facilitate transcription initiation by binding to RNA polymerase.

Sensing and Signal Transduction

The mechanisms by which cells respond to environmental signals.

Transcription Regulation in Archaea

Similar to bacterial regulation but often involves different proteins and factors.

Methyl-accepting Chemotaxis Proteins (MCPs)

Sensory proteins in bacteria that sense changes in attractants and repellents.

Inducer Exclusion

A mechanism where glucose prevents the transport of lactose into the cell.

Diauxic Growth

A biphasic growth pattern when two carbon sources are available.

Arabinose Operon

A set of genes that is regulated together for metabolizing arabinose.

Lac Operon

The operon required for the metabolism of lactose in bacteria.

Nutrient Limitation

A condition that limits the growth and function of organisms.

Pathogenicity Island

Large genomic regions in bacteria that are responsible for virulence.

RpoS Regulon

A set of genes regulated by the stationarity sigma factor RpoS.

Patho-Systems

Systems of genes responsible for pathogenic traits.

Cyclic Nucleotide Regulation

Control mechanisms involving cyclic nucleotides like cAMP.

Genetic Regulation

The control of gene expression levels through various mechanisms.

Transcriptional Attenuation

Mechanism for regulating gene expression by premature termination of transcription.

RNA-Based Regulation

Regulatory mechanisms involving noncoding RNAs and their interaction with mRNAs.

Biosynthetic Pathway Control

Mechanisms that regulate the synthesis of biomolecules.

Chemical Gradients

Gradients in the concentration of substances affecting cell behavior.

Amino Acid Biosynthesis

The metabolic process by which cells produce amino acids.

Protein-DNA Interactions

The binding of proteins to DNA, affecting gene regulation.

Operonic Regulation

The control of gene expression through operon arrangements.

Regulatory RNAs

Noncoding RNAs that play a role in controlling gene expression.

Signal Reception

The detection of external signals by cellular receptors.

Cosmopolitan Genes

Genes with widespread regulatory functions across different systems.

Biofilm Formation

The process of microbial communities attaching to surfaces and creating a protective layer.

Transcriptional Activators

Proteins that increase the transcription rate of specific genes.

Transcriptional Repressors

Proteins that decrease the transcription rate of specific genes.

Homeostatic Regulation

Maintaining stable internal conditions despite external changes.

Dimerization

The process by which two proteins bind together to form a dimer.

Maltose Operon

The operon necessary for the metabolism of maltose.

Autophosphorylation

The process by which a kinase enzyme phosphorylates itself.

Transcriptional Blockade

The prevention of transcription initiation by regulatory proteins.

RNA Polymerase Binding

The attachment of RNA polymerase to a DNA strand to start transcription.

Transcription Start Site

The location on the DNA where RNA synthesis begins.

Bioinformatics Approaches

Techniques using computational methods for analyzing biological data.

Mutagenesis

The process of generating mutations in the DNA sequence.

Polycistronic mRNA

mRNA that encodes multiple proteins, typical in prokaryotes.

Inhibitory Mechanism

Processes that reduce the activity of gene expression.

Nucleic Acid Binding Domens

Regions of proteins that interact with DNA or RNA.

Regulatory Feedback

Processes that allow for self-regulation of metabolic pathways.

Carrying Capacity

The maximum population size that an environment can sustain.

Phenotypic Expression

The observable characteristics determined by genetic information.