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bioRxiv · 10.1101/2020.10.30.362657

Identifying virulence determinants of multidrug-resistant Klebsiella pneumoniae in Galleria mellonella

Bruchmann, S.·Feltwell, T.·Parkhill, J.·Short, F.
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Abstract

Infections caused by Klebsiella pneumoniae are a major public health threat. Extensively drug-resistant and even pan-resistant strains have been reported. Understanding K. pneumoniae pathogenesis is hampered by the fact that murine models of infection offer limited resolution for the non-hypervirulent strains which cause the majority of infections. We have performed genome-scale fitness profiling of a multidrug-resistant K. pneumoniae ST258 strain during infection of the insect Galleria mellonella, with the aim to determine if this model is suitable for large-scale virulence factor discovery in this pathogen. Our results demonstrated a dominant role for surface polysaccharides in infection, with contributions from siderophores, cell envelope proteins, purine biosynthesis genes and additional genes of unknown function. Comparison with a hypervirulent strain, ATCC 43816, revealed substantial overlap in important infection-related genes, as well as additional putative virulence factors that may be specific to ST258. Our analysis also identified a role for the metalloregulatory protein NfeR (also called YqjI) in virulence. Overall, this study offers new insight into the infection fitness landscape of K. pneumoniae ST258, and provides a framework for using the highly flexible, scalable G. mellonella infection model to dissect the molecular virulence mechanisms of K. pneumoniae and other bacterial pathogens.

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Bruchmann, S., Feltwell, T., Parkhill, J., Short, F.. 2020-10-31. Identifying virulence determinants of multidrug-resistant Klebsiella pneumoniae in Galleria mellonella. https://doi.org/10.1101/2020.10.30.362657

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