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bioRxiv · 10.1101/2023.06.27.546803

Identifying molecular targets of a colloidal nanosilver formulation (Silversol) in multidrug resistant Pseudomonas aeruginosa

Gajera, G.·Thakkar, N.·Godse, C.·DeSouza, A.·Mehta, D.·Kothari, V.
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Abstract

P. aeruginosa is a notorious pathogen. A multi-drug resistant strain of this bacterium was challenged with a colloidal nano-silver formulation- Silversol(R). Its minimum inhibitory concentration against P. aeruginosa was found to be 1.5 ppm, and at sub-MIC of 1 ppm, it was able to alter quorum-sensing regulated pigmentation, exopolysaccharide synthesis and biofilm formation, antibiotic susceptibility, protein synthesis and export, nitrogen metabolism, and siderophore production in this pathogen. Transcriptome analysis of the silver-exposed P. aeruginosa indicated generation of nitrosative stress and disturbance of iron homeostasis to be the major mechanisms associated with anti-Pseudomonas activity of Silversol(R). Network analysis of the differentially expressed genes in silver-treated bacterium identified ten genes as the potential molecular targets: norB, norD, nirS, nirF, nirM, nirQ, nosZ, nosY, narK1, and norE (all associated with nitrogen metabolism or denitrification). Three of them (norB, narK1, and norE) were also validated through RT-PCR.

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Gajera, G., Thakkar, N., Godse, C., DeSouza, A., Mehta, D., Kothari, V.. 2023-06-28. Identifying molecular targets of a colloidal nanosilver formulation (Silversol) in multidrug resistant Pseudomonas aeruginosa. https://doi.org/10.1101/2023.06.27.546803

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