Related Experiment Video

Updated: Dec 28, 2025

Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds
06:36

Improved Enzyme Protection Assay to Study Staphylococcus aureus Internalization and Intracellular Efficacy of Antimicrobial Compounds

Published on: September 8, 2021

3.2K

Polyketides from marine-derived Aspergillus welwitschiae inhibit Staphylococcus aureus virulence factors and

Luciana A Loges1, Denise B Silva2, Gustavo V B Paulino3

  • 1Laboratório de Biofilmes e Diversidade Microbiana (LABDIM), Faculdade de Farmácia and Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul (UFRGS). Av. Ipiranga, 2752, 90610-000, Porto Alegre, Rio Grande do Sul, Brazil.

Microbial Pathogenesis
|February 19, 2020
PubMed

Insights

Natural compounds from Aspergillus welwitschiae show anti-virulence effects against Staphylococcus aureus, reducing biofilm formation and hemolysis. These compounds, combined with vancomycin, offer potential new strategies for combating antibiotic-resistant bacterial infections.

Area of Science:

  • Microbiology
  • Natural Product Chemistry
  • Pharmacology

Background:

  • Staphylococcus aureus is a significant cause of hospital and community infections, with rising antibiotic resistance.
  • S. aureus infections often involve biofilms and virulence factors, making them challenging to treat.
  • Targeting virulence factors offers a strategy to reduce selective pressure for antibiotic resistance.

Purpose of the Study:

  • To investigate the anti-virulence potential of naphtho-γ-pyrones from Aspergillus welwitschiae against Staphylococcus aureus.
  • To characterize the chemical constituents of the isolated compounds.
  • To evaluate the efficacy of these compounds, alone and in combination with vancomycin, in a model of staphylococcal infection.

Main Methods:

  • Extraction and isolation of naphtho-γ-pyrones from Aspergillus welwitschiae mycelium.
  • Chemical characterization using Liquid Chromatography-Diode Array Detection (LC-DAD) and Liquid Chromatography-Mass Spectrometry (LC-MS).
  • Assessment of anti-virulence activities including biofilm inhibition, hemolysis, and coagulation assays.
  • In vivo efficacy testing using the Galleria mellonella infection model, with and without vancomycin.

Main Results:

  • Naphtho-γ-pyrones demonstrated significant anti-virulence activity against Staphylococcus aureus, including a Methicillin-resistant Staphylococcus aureus (MRSA) clinical isolate.
  • Observed reduction in biofilm formation, hemolysis, and coagulation promoted by S. aureus.
  • Combination therapy with vancomycin showed enhanced protection against staphylococcal infection in the Galleria mellonella model.

Conclusions:

  • Natural products, specifically naphtho-γ-pyrones from Aspergillus welwitschiae, represent a promising source for novel anti-virulence agents against Staphylococcus aureus.
  • Anti-virulence strategies and combination therapies offer potential alternatives for managing antibiotic-resistant bacterial infections.
  • Further research into these compounds could lead to new therapeutic approaches for staphylococcal infections.
Keywords:
AspergillusBiofilmNaphto-γ-pyroneStaphylococcus aureusVirulence

More Related Videos

Nanomechanics of Drug-target Interactions and Antibacterial Resistance Detection11:56

Nanomechanics of Drug-target Interactions and Antibacterial Resistance Detection

Published on: October 25, 2013

14.6K
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

1.4K

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,...
423
Antimicrobial Proteins01:23

Antimicrobial Proteins

Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
12.8K
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...
6.6K
Development of Antibiotic Resistance01:30

Development of Antibiotic Resistance

Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
1.0K
Antimicrobial Effectiveness01:28

Antimicrobial Effectiveness

The effectiveness of antimicrobial agents depends on various factors influencing their ability to eliminate microbial populations. Larger microbial populations require more time for complete eradication, emphasizing the importance of population size analysis when evaluating antimicrobial efficacy.Microbial resistance to antimicrobial agents varies significantly. Highly resilient microorganisms include endospores, gram-negative bacteria, and non-enveloped viruses, while prions are exceptionally...
850