Related Experiment Video
Updated: May 12, 2026
11:30
A Molecular Readout of Long-term Olfactory Adaptation in C. elegans
Published on: December 22, 2012
Prolonged stimuli alter the bacterial chemosensory clusters
1The Racah Institute of Physics, The Hebrew University, Jerusalem, 91904, Israel.
Molecular Microbiology
|April 5, 2013
Summary
Bacterial chemosensory clusters, crucial for environmental navigation, exhibit stimulus-induced dynamics. Receptor packing decreases with stimuli and recovers upon removal, revealing plasticity in these essential biological clusters.
Area of Science:
- Microbiology
- Biophysics
- Cell Biology
Background:
- Membrane-bound receptor clustering is vital in biological systems.
- Bacterial chemosensory clusters enable navigation along chemical gradients.
- The dynamic behavior of these clusters remains poorly understood.
Purpose of the Study:
- To investigate the dynamic nature of bacterial chemosensory clusters.
- To understand how stimuli affect receptor cluster organization and function.
- To reveal stimulus-dependent plasticity in chemoreceptor clusters.
Main Methods:
- Utilized fluorescence polarization measurements in live Escherichia coli.
- Employed time-lapse fluorescence imaging.
- Analyzed changes in receptor packing and cluster dissociation.
Main Results:
- Stimulus application leads to a slow decrease in receptor packing.
- Receptor packing recovers upon stimulus removal.
- Effective kinase response cooperativity evolves with stimulus presence.
- Receptor clusters generally do not dissociate upon ligand binding.
Conclusions:
- Chemosensory clusters exhibit stimulus-induced dynamics and plasticity.
- Physical changes in receptor packing correlate with altered kinase response.
- Cluster integrity is maintained despite ligand binding.
Related Concept Videos
01:27Chemotaxis in E. coli
Chemotaxis in Escherichia coli is a sensory-driven motility mechanism that enables bacteria to navigate chemical gradients, moving toward beneficial environments while avoiding harmful conditions. This process relies on a signal transduction system integrating external chemical cues with flagellar motor control.Chemoreceptors and Signal DetectionE. coli detects chemical gradients through methyl-accepting chemotaxis proteins (MCPs), which are membrane-bound chemoreceptors that sense attractants...
01:30Bacterial Signaling
Bacterial signaling can occur within bacteria (intracellular) or between bacteria (intercellular). At times, a group of bacteria behaves like a community. To achieve this, they engage in quorum sensing, the perception of higher cell density that causes changes in gene expression. Quorum sensing involves both extracellular and intracellular signaling. The signaling cascade starts with a molecule called an autoinducer (AI). Individual bacteria produce AIs that move out of the bacterial cell...
01:12GPCR Desensitization
G protein-coupled receptor (GPCR) signaling plays a crucial role in cell functioning. GPCR desensitization is an equally essential process. It allows cells to respond to changing environments and regain sensitivity to new stimuli while preventing unnecessary stimulation when no longer needed. Prolonged exposure to stimuli leads to GPCR desensitization. It involves blocking the receptors from binding and activating additional G proteins. This inhibits activation of downstream effectors, thereby...
01:28Gene Regulation in Microbial Communities: Quorum Sensing
Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
01:23Stringent Response in E. coli
Bacterial growth is closely tied to nutrient availability, with cells proliferating exponentially under favorable conditions and entering a stationary phase when resources become scarce. This transition is mediated by a regulatory mechanism known as the stringent response, which allows bacteria to adapt to nutrient deprivation by modulating gene expression and metabolic activity.During nutrient scarcity, intracellular amino acid levels decline. It results in the accumulation of uncharged tRNAs...
01:30Other Stress Responses in Bacteria
Bacteria have global regulatory systems that control several types of stress mechanisms. These include Pho regulon and the heat shock response, which are essential systems for environmental adaptation, such as nutrient limitation and proteotoxic stress. The Pho regulon and the heat shock response exemplify bacterial resilience, enabling rapid adaptation to fluctuating environmental conditions.Pho RegulonBacteria require phosphorus for essential cellular processes, including nucleic acid...