Deciphering the function of Com_YlbF domain-containing proteins in Staphylococcus aureus.

Rozo, Z. L. C.; Ortiz, R. A. M.; Romero, M. L. V.; Riano, D. A.; Madronero, L. J.; Gomez, L. F. P.; Gomez, G. N. V.; Martinez, B. G.; Sarasua, M. E.; Pelaez, M. A. C.; Olaya, J. C.; Morales, L.; Clavijo, C. N.; Perez, J. A. E.

doi:10.1101/2024.11.14.623514

bioRxiv · 10.1101/2024.11.14.623514

Deciphering the function of Com_YlbF domain-containing proteins in Staphylococcus aureus.

Rozo, Z. L. C.·Ortiz, R. A. M.·Romero, M. L. V.·Riano, D. A.·Madronero, L. J.·Gomez, L. F. P.·Gomez, G. N. V.·Martinez, B. G.·Sarasua, M. E.·Pelaez, M. A. C.·Olaya, J. C.·Morales, L.·Clavijo, C. N.·Perez, J. A. E.

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Abstract

The com_ylbF domain-containing proteins that inhibit sporulation, competition, and biofilm formation by affecting the activity of Ribonuclease RNase-Y in Bacillus subtilis. Similar Com_YlbF proteins are found in Staphylococcus aureus, but their function is yet to be determined. This study investigates the role of com_ylbF domain-containing proteins (Qrp/YheA, YmcA, and YlbF) in S. aureus by evaluating the impact of qrp/yheA, ymcA, and ylbF gene deletion on biofilm formation, PIA/PNAG production, and hemolytic capacity. It was found that deletion of the three qrp/yheA, ymcA, and ylbF genes in S. aureus produced a decrease in biofilm formation, a slight decrease in PIA/PNAG production, and a decrease in its hemolytic capacity. Global transcriptional analysis in the mutant strain showed dysregulation of several genes associated with pathogenesis, notably a decreased expression of the agrA gene (quorum sensing system), the delta, alpha, and gamma hemolysins, as well as the sdrC genes, eap/map (adhesion proteins). It also showed-an attenuation of virulence, manifesting as enhanced survival among Galleria mellonella larvae, and BALB/c mice, possibly associated due to disrupted RNase-Y activity when the qrp/yheA, ymcA, and ylbF are deleted. In conclusion, this work supports the hypothesis that this new family of proteins containing a com_ylbF domain is involved in the regulation of genes related to biofilm formation, hemolysis, and virulence in S. aureus through a change in RNase-Y activity.

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Rozo, Z. L. C., Ortiz, R. A. M., Romero, M. L. V., Riano, D. A., Madronero, L. J., Gomez, L. F. P., Gomez, G. N. V., Martinez, B. G., Sarasua, M. E., Pelaez, M. A. C., Olaya, J. C., Morales, L., Clavijo, C. N., Perez, J. A. E.. 2024-11-15. Deciphering the function of Com_YlbF domain-containing proteins in Staphylococcus aureus.. https://doi.org/10.1101/2024.11.14.623514

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