Related Experiment Video

Updated: Mar 17, 2026

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

3.3K

Intracellular activity of a membrane-active glycopeptide antibiotic against meticillin-resistant Staphylococcus

Venkateswarlu Yarlagadda1, Sandip Samaddar1, Jayanta Haldar1

  • 1Chemical Biology and Medicinal Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India.

Journal of Global Antimicrobial Resistance
|July 21, 2016
PubMed

Insights

The novel antibiotic Van-QC8 effectively kills intracellular methicillin-resistant Staphylococcus aureus (MRSA) within macrophages. This compound shows superior activity to vancomycin and linezolid, offering a promising new treatment for severe bacterial infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pharmacology

Background:

  • Staphylococcus aureus is a significant intracellular pathogen, posing treatment challenges due to limited therapeutic options for severe infections.
  • Drug-resistant strains, such as methicillin-resistant S. aureus (MRSA), exacerbate the need for novel antimicrobial agents.
  • Van-QC8, a lipophilic vancomycin analogue, exhibits potent activity against resistant Gram-positive bacteria.

Purpose of the Study:

  • To evaluate the intracellular bactericidal activity of Van-QC8 against MRSA.
  • To investigate the cellular uptake mechanisms of Van-QC8.
  • To compare the efficacy of Van-QC8 with existing antibiotics like vancomycin and linezolid against intracellular MRSA.

Main Methods:

  • RAW macrophages were infected with MRSA to assess intracellular bacterial load.
  • Time- and concentration-dependent killing assays were performed using Van-QC8.
  • Cellular uptake pathways for Van-QC8 were elucidated using endocytosis inhibitors.

Main Results:

  • Van-QC8 demonstrated potent time- and concentration-dependent bactericidal activity against intracellular MRSA.
  • Van-QC8 exhibited significantly enhanced intracellular efficacy compared to vancomycin and linezolid.
  • Cellular uptake of Van-QC8 occurred via multiple endocytic pathways, including clathrin-dependent/independent and caveolin-dependent/independent routes.

Conclusions:

  • Van-QC8 is a highly effective agent against intracellular MRSA infections in macrophages.
  • The multifaceted uptake mechanism contributes to Van-QC8's potent intracellular activity.
  • Van-QC8 holds potential for clinical translation in treating severe intracellular bacterial infections.
Keywords:
GlycopeptidesIntracellular activityMRSAMembrane-active antibioticMeticillin-resistant Staphylococcus aureus

More Related Videos

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria14:04

Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria

Published on: May 8, 2013

25.3K
Development and Assessment of Intracellular Infection Models for Staphylococcus aureus08:32

Development and Assessment of Intracellular Infection Models for Staphylococcus aureus

Published on: January 17, 2025

1.4K

Related Concept Videos

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...
15.2K
Defense Against Bacterial Pathogens01:31

Defense Against Bacterial Pathogens

The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
3.3K
Surface Membrane Barriers01:18

Surface Membrane Barriers

The skin and mucous membranes serve as the primary line of defense against pathogens by providing both physical and chemical protection. These barriers are essential in preventing the entry and establishment of microbes, thereby maintaining the integrity of the host.
The outer layer of the skin, the epidermis, is a robust barrier comprising layers of closely packed keratinized cells. This dense arrangement prevents microbes from penetrating the body. The periodic shedding of epidermal cells...
3.3K
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...
1.9K