Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Gene Regulation in Microbial Communities: Quorum Sensing01:28

Gene 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,...
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
Bacterial Signaling01:30

Bacterial 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...
Colonisation of Pathogens01:25

Colonisation of Pathogens

Pathogen colonization of host tissues is a critical step in the development of infectious diseases. Various pathogenic microorganisms, including bacteria, fungi, viruses, and protozoa, have evolved complex strategies to attach to, invade, and persist within host environments. These mechanisms enable pathogens to establish infections, evade immune responses, and resist antimicrobial treatments.Attachment to Host CellsIn bacteria, colonization typically begins with adherence to host epithelial...
Global Regulatory Systems01:28

Global Regulatory Systems

Global regulatory systems in bacteria enable rapid and coordinated responses to environmental changes by integrating sensory inputs with gene expression, ensuring efficient adaptation to fluctuating conditions. Key global regulatory mechanisms include regulons, two-component systems, sigma factors, and secondary messengers.Regulons and Global RegulatorsA regulon is a collection of genes and operons controlled by a common global regulator. These regulators enable bacteria to prioritize resource...
Bacterial Toxins01:12

Bacterial Toxins

Bacterial toxins are sophisticated virulence factors that enable pathogenic bacteria to interact with, invade, and damage host tissues. These toxins fall broadly into two types: protein exotoxins, which are secreted into the environment and target specific host receptors, and lipopolysaccharide endotoxins, which are structural components of the bacterial outer membrane released primarily during bacterial lysis or membrane shedding. Exotoxins generally act more selectively, binding to cell...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Breast implant surface texture is associated with distinct implant microbiome profiles in humans.

Acta biomaterialia·2026
Same author

Social immunity can be a consequence and cause of social evolution.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

Cytoplasmic flow dynamics in arbuscular mycorrhizal fungi are intrinsic and independent of plant hosts.

Fungal biology·2026
Same author

Symbiotic fungi underlie the regeneration potential of island rainforests.

Current biology : CB·2026
Same author

A murine sinonasal infection model recapitulates key features of clinical chronic rhinosinusitis.

Journal of medical microbiology·2026
Same author

An insect that cooperates like bacteria.

Proceedings of the National Academy of Sciences of the United States of America·2026

Related Experiment Video

Updated: May 21, 2026

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
07:10

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

Published on: February 19, 2019

Kin selection, quorum sensing and virulence in pathogenic bacteria.

Kendra P Rumbaugh1, Urvish Trivedi, Chase Watters

  • 1Department of Surgery, Texas Tech University Health Sciences Center, Lubbock, TX 79430, USA.

Proceedings. Biological Sciences
|June 1, 2012
PubMed
Summary

Quorum sensing (QS) enhances bacterial growth and virulence. High relatedness favors cooperative QS, increasing virulence, while low relatedness benefits non-cooperative mutants, revealing an inverse relationship between relatedness and virulence.

More Related Videos

Coincubation Assay for Quantifying Competitive Interactions between Vibrio fischeri Isolates
07:43

Coincubation Assay for Quantifying Competitive Interactions between Vibrio fischeri Isolates

Published on: July 22, 2019

Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
07:47

Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases

Published on: January 1, 2016

Related Experiment Videos

Last Updated: May 21, 2026

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues
07:10

A Fluorescence-based Method to Study Bacterial Gene Regulation in Infected Tissues

Published on: February 19, 2019

Coincubation Assay for Quantifying Competitive Interactions between Vibrio fischeri Isolates
07:43

Coincubation Assay for Quantifying Competitive Interactions between Vibrio fischeri Isolates

Published on: July 22, 2019

Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
07:47

Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases

Published on: January 1, 2016

Area of Science:

  • Microbiology
  • Evolutionary Biology
  • Bacterial Pathogenesis

Background:

  • Bacterial cooperative behaviors, such as the release of extracellular factors, are often regulated by quorum sensing (QS).
  • QS allows bacteria to coordinate gene expression based on population density, influencing virulence and growth within hosts.
  • Understanding the evolution of cooperation and its impact on virulence is crucial in microbial ecology.

Purpose of the Study:

  • To investigate how quorum sensing (QS) evolves under varying conditions of bacterial relatedness (strain diversity) within a host.
  • To determine the consequences of QS evolution on bacterial virulence in an in vivo model.
  • To examine the interplay between bacterial relatedness, cooperation, and virulence.

Main Methods:

  • An in vivo selection experiment was conducted using mice.
  • Two bacterial strains were used: a wild-type strain that produces and responds to QS signals, and a lasR mutant that is signal-blind and does not release QS-dependent factors.
  • Bacterial populations with varying degrees of relatedness were monitored for growth, frequency of strains, and virulence.

Main Results:

  • Quorum sensing (QS) significantly enhances bacterial growth within hosts.
  • High relatedness among bacterial strains favors the cooperative QS wild-type strain.
  • Low relatedness favors the lasR mutant, which exploits the cooperative behaviors of the wild-type, increasing its own frequency.
  • Increased relatedness led to higher bacterial growth and, consequently, higher virulence, contrary to typical virulence theory predictions.

Conclusions:

  • Bacterial relatedness is a key factor shaping the evolution of cooperative traits like quorum sensing (QS).
  • Cooperative QS enhances bacterial growth and virulence, particularly under high relatedness conditions.
  • The study reveals an inverse relationship between bacterial relatedness and virulence, challenging established virulence theory.