Related Experiment Video
Updated: Nov 14, 2025
11:45
Fluorescence Live-cell Imaging of the Complete Vegetative Cell Cycle of the Slow-growing Social Bacterium Myxococcus xanthus
Published on: June 20, 2018
9.8K
A Small Molecule Coordinates Symbiotic Behaviors in a Host Organ
Katherine E Zink1, Denise A Ludvik2,3, Phillip R Lazzara1
1Department of Pharmaceutical Sciences, University of Illinois at Chicago, Chicago, Illinois, USA.
Mbio
|March 10, 2021
Summary
Researchers identified a novel molecule, cyclo(d-histidyl-l-proline), that influences the symbiotic relationship between Hawaiian bobtail squid and Vibrio fischeri bacteria. This diketopiperazine impacts bacterial biofilm formation and luminescence, crucial for microbiome establishment.
Area of Science:
- Microbiology
- Chemical Biology
- Marine Biology
Background:
- The Hawaiian bobtail squid (Euprymna scolopes) and its symbiont Vibrio fischeri form a simplified model for microbiome research.
- Precise molecular communication is essential for initiating the specific symbiotic relationship, as squid acquire symbionts from the environment.
- Specialized metabolites likely modulate microbial processes within the squid's light organ.
Purpose of the Study:
- To identify small molecules influencing the establishment of the Euprymna scolopes-Vibrio fischeri symbiosis.
- To analyze metabolite production in V. fischeri strains with altered biofilm formation.
- To investigate the role of identified metabolites in modulating bacterial behavior and symbiosis.
Main Methods:
- Utilized imaging mass spectrometry to analyze metabolite production in V. fischeri mutants.
- Compared metabolite profiles of "biofilm-up" and "biofilm-down" mutants against a wild-type strain.
- Employed structural elucidation and synthetic chemistry to identify and characterize signaling molecules.
Main Results:
- Identified a diketopiperazine, cyclo(d-histidyl-l-proline), as a key metabolite produced by biofilm-up V. fischeri mutants.
- Demonstrated that this diketopiperazine modulates V. fischeri luminescence.
- Detected cyclo(d-histidyl-l-proline) directly within the light organ of colonized E. scolopes.
Conclusions:
- Cyclo(d-histidyl-l-proline) plays a role in modulating V. fischeri luminescence and is present in the host light organ.
- This finding highlights the importance of small molecules in host-microbe interactions and microbiome development.
- The squid-Vibrio system is a valuable model for discovering and characterizing microbial signaling molecules.
Related Concept Videos
00:58Symbiosis
35.7K
Symbiotic relationships are long-term, close interactions between individuals of different species that affect the distribution and abundance of those species. When a relationship is beneficial to both species, this is called mutualism. When the relationship is beneficial to one species but neither beneficial nor harmful to the other species, this is called commensalism. When one organism is harmed to benefit another, the relationship is known as parasitism. These types of relationships often...
35.7K
01:32Cytoskeletal Coordination in Cell Migration
5.1K
A migrating cell changes its shape during the cyclic events of attachment and detachment from the substratum and repositions the cell organelles correspondingly. These complex events are orchestrated by the dynamic cytoskeletal network comprising actin filaments, intermediate filaments, and microtubules. Cytoskeletal crosstalk — the direct and indirect communication between the different components — is crucial for this coordination. Direct communication involves various linker...
5.1K
01:27Chemotaxis in E. coli
350
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...
350
01:30Bacterial Signaling
38.5K
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...
38.5K
01:23Overview of Cell Signaling
22.8K
Despite the protective membrane that separates a cell from the environment, cells need the ability to detect and respond to environmental changes. Additionally, cells often need to communicate with one another. Unicellular and multicellular organisms use a variety of cell signaling mechanisms to communicate with the environment.
Cells respond to many types of information, often through receptor proteins positioned on the membrane. For example, skin cells respond to and transmit touch...
Cells respond to many types of information, often through receptor proteins positioned on the membrane. For example, skin cells respond to and transmit touch...
22.8K
01:28Gene Regulation in Microbial Communities: Quorum Sensing
220
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,...
220