Linoleic acid acts as a potential anti-virulence agent in Klebsiella pneumoniae

The rise in antimicrobial resistance among bacterial pathogens is a global concern, and anti-virulence therapy may be an alternative strategy to address the issue. Multidrug resistant (MDR) hypervirulent Klebsiella pneumoniae (HvKp) is known to be associated with healthcare associated infections. These are often challenging to treat and here anti-virulence therapy may be a treatment option. The study of anti-virulence compounds against HvKp by in-silico prediction, in-vitro experiments and in-vivo assay enables to determine which anti-virulence compounds are suitable for an alternative approach MDR HvKp.

Modeling of the proteins, ligand binding and molecular docking were performed targeting different hypervirulence genes viz., rmpA, rmpA2 and, iroC by in-silico analysis using different bioinformatics tool and software. Minimum inhibitory concentration (MIC) was determined for six anti-virulence compounds; curcumin, eugenol, reserpine, linoleic acid, ε-anethole, and α-thujone by standard protocol. Quantitative real-time PCR was performed selecting two isolates harboring rmpA, rmpA2 and iroC genes. Galleria mellonella larva killing assay was used for in-vivo experiment.

In-silico analysis observed that linoleic acid could be the best fit in comparison with the other compounds. None of the anti-virulence compounds showed any inhibitory activity and upon transcriptional expression analysis of the hypervirulence genes; rmpA was marginally increased for both the isolates when linoleic acid exposure was given.

In-vivo study revealed that linoleic acid and reserpine showed anti-virulence activity.