Related Experiment Video

Updated: May 4, 2026

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

11.3K

Solonamide B inhibits quorum sensing and reduces Staphylococcus aureus mediated killing of human neutrophils

Anita Nielsen1, Maria Månsson2, Martin S Bojer1

  • 1Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.

Plos One
|January 14, 2014
PubMed

Insights

Marine bacterium Solonamide B disrupts Staphylococcus aureus (MRSA) virulence. This compound inhibits the agr quorum sensing system, reducing toxins and decreasing USA300 strain infection severity.

Area of Science:

  • Microbiology
  • Marine Biology
  • Pathogen Research

Background:

  • Methicillin-resistant Staphylococcus aureus (MRSA), particularly community-associated (CA)-MRSA USA300, causes severe infections.
  • The agr quorum sensing system regulates MRSA virulence factors.
  • Solonamide B, a cyclodepsipeptide from Photobacterium halotolerans, was previously shown to reduce RNAIII expression.

Purpose of the Study:

  • To investigate Solonamide B's mechanism of action on the agr system.
  • To evaluate Solonamide B's effect on MRSA USA300 virulence factors and toxicity.

Main Methods:

  • Investigated Solonamide B's interference with autoinducing peptide (AIP) binding to AgrC.
  • Assessed Solonamide B's impact on alpha-hemolysin activity and PSM transcription in USA300.
  • Measured the toxicity of USA300 supernatants on human neutrophils and rabbit erythrocytes.

Main Results:

  • Solonamide B inhibits the binding of AIPs to AgrC, disrupting the agr quorum sensing system.
  • Solonamide B significantly reduced alpha-hemolysin activity and PSM transcription in MRSA USA300.
  • Supernatant toxicity was reduced by 80% towards human neutrophils and rabbit erythrocytes.

Conclusions:

  • Solonamide B is the first reported natural compound from a marine Gram-negative bacterium to interfere with MRSA agr quorum sensing.
  • Solonamide B effectively reduces MRSA USA300 virulence gene expression and associated toxicity.

More Related Videos

Quantification of Violacein in Chromobacterium violaceum and Its Inhibition by Bioactive Compounds07:13

Quantification of Violacein in Chromobacterium violaceum and Its Inhibition by Bioactive Compounds

Published on: August 8, 2025

1.8K
Author Spotlight: Advancing Therapeutics to Treat Vibriosis in Humans and Aquatic Organisms03:29

Author Spotlight: Advancing Therapeutics to Treat Vibriosis in Humans and Aquatic Organisms

Published on: May 31, 2024

1.1K

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,...
954
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...
29.8K
Clinical Significance of Antibiotic Resistance01:25

Clinical Significance of Antibiotic Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within...
90
Inhibitors of Bacterial Protein Synthesis01:25

Inhibitors of Bacterial Protein Synthesis

Aminoglycosides constitute a highly potent class of bactericidal antibiotics that exert their antimicrobial effects by targeting the bacterial ribosome, specifically disrupting protein synthesis. These polycationic molecules consist of amino-modified sugars linked via glycosidic bonds to an aminocyclitol core such as 2-deoxystreptamine or streptamine. Their strong positive charges facilitate tight binding to the negatively charged phosphate backbone of ribosomal RNA (rRNA), primarily at the 16S...
106
Inhibitors of Bacterial DNA Synthesis01:28

Inhibitors of Bacterial DNA Synthesis

Bacterial pathogens depend on precise and efficient DNA replication to sustain infection. Two type II topoisomerases—DNA gyrase and topoisomerase IV—are critical to this process, as they resolve DNA supercoiling and unlink chromosomes during replication. Fluoroquinolones, synthetic derivatives of quinolones, exploit this mechanism by stabilizing the transient DNA–enzyme cleavage complex, preventing strand religation, and causing lethal double-strand breaks. These...
130
Combined Effects of Drugs: Synergism01:27

Combined Effects of Drugs: Synergism

Synergism is a useful mechanism where combining two or more drugs is more effective than each constituent used alone. Such combinations are also called supra-additive interactions. The drugs collectively enhance the final therapeutic effect by acting on different targets. Another advantage is that the low dose of each constituent drug is sufficient to achieve the desired effect. This helps reduce the duration of therapy and lower the adverse effects of these drugs.
Such synergistic combinations...
6.2K