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bioRxiv · 10.1101/714725

Uncovering Staphylococcus aureus genes with roles in pathogenicity by silkworm infection model

Paudel, A.·Hamamoto, H.·Panthee, S.·Matsumoto, Y.·Sekimizu, K.
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Abstract

The regulatory network of virulence factors production by Staphylococcus aureus, an opportunistic pathogen, is incompletely understood, and the functions of many uncharacterized genes in its genome remain to be uncovered. We screened 380 function unassigned genes disrupted mutants of the community-acquired methicillin-resistant S. aureus USA300 for pathogenicity using silkworms and identified 11 strains with reduced silkworm killing ability. Nine out of the 11 strains displayed reduced virulence in the mouse model as evidenced by reduced colony-forming units in organs of the infected mice. Three of the identified gene-disrupted mutants had reduced hemolytic activity, one among the three also had reduced proteolytic activity and pigment production. These results suggest that silkworm model could identify the genes required for virulence in the mouse model. The newly identified genes involved in virulence in this study facilitates the further understanding of the pathogenicity of S. aureus.\n\nImportanceWe performed a large scale screening of mutants of Staphylococcus aureus with disruption in function unassigned genes using silkworm infection model and identified eleven genes required for full virulence in silkworm. Nine of the eleven genes were involved in virulence in mice and were previously not known to aggravate virulence of S. aureus. The results suggest that silkworm model is suitable for quantitative measurement of virulence, which is shared between silkworms and mammals.

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Paudel, A., Hamamoto, H., Panthee, S., Matsumoto, Y., Sekimizu, K.. 2019-07-25. Uncovering Staphylococcus aureus genes with roles in pathogenicity by silkworm infection model. https://doi.org/10.1101/714725

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