Bactericidal Activity of Selenium Nanoparticles Against a Multidrug-Resistant Pathogen: Mechanistic Hypothesis from...

Area of Science:

• Nanotechnology
• Microbiology
• Biochemistry

Background:

• Antimicrobial resistance (AMR) is a global health crisis demanding new therapeutic agents.
• Selenium nanoparticles (SeNPs) show potential as antimicrobials, but their mechanisms of action are not fully understood.
• Developing novel strategies to combat multidrug-resistant pathogens is crucial.

Purpose of the Study:

• To elucidate the antibacterial mechanism of green-synthesized selenium nanoparticles (SeNPs).
• To investigate the effects of SeNPs on key cellular processes in multidrug-resistant *E. coli*.
• To propose a mechanistic hypothesis for SeNP-mediated bacterial cell death.

Main Methods:

• Green synthesis of SeNPs using ascorbic acid and sodium citrate.
• Characterization of SeNPs (size, stability, crystallinity).
• Phenotypic analysis combined with preliminary proteomic profiling to identify affected cellular pathways.

Main Results:

• SeNPs exhibited potent bactericidal activity against multidrug-resistant *E. coli*.
• SeNPs induced significant oxidative stress and depleted key components of the glutathione antioxidant system.
• SeNPs severely suppressed enzymes involved in central energy metabolism (TCA cycle) and impaired oxidative phosphorylation.

Conclusions:

• SeNPs exert a dual-action antimicrobial effect by inducing oxidative stress and disrupting energy metabolism.
• The combined disruption leads to metabolic paralysis and bacterial cell death.
• SeNPs represent a promising candidate for a multi-targeted antimicrobial strategy against resistant pathogens.