The H-NS Regulator Plays a Role in the Stress Induced by Carbapenemase Expression in Acinetobacter baumannii

Fanny Huang, Noelle Fitchett, Chelsea Razo-Gutierrez, Casin Le, Jasmine Martinez, Grace Ra, Carolina Lopez, Lisandro J. Gonzalez, Rodrigo Sieira, Alejandro J. Vila, Robert A. Bonomo, Maria Soledad Ramirez (+1 others)
2020 mSphere  
Disruption of the histone-like nucleoid structuring protein (H-NS) was shown to affect the ability of Gram-negative bacteria to regulate genes associated with virulence, persistence, stress response, quorum sensing, biosynthesis pathways, and cell adhesion. Here, we used the expression of metallo-β-lactamases (MBLs), known to elicit envelope stress by the accumulation of toxic precursors in the periplasm, to interrogate the role of H-NS in Acinetobacter baumannii, together with other stressors.
more » ... Using a multidrug-resistant A. baumannii strain, we observed that H-NS plays a role in alleviating the stress triggered by MBL toxic precursors and counteracts the effect of DNA-damaging agents, supporting its role in stress response. IMPORTANCE Carbapenem-resistant A. baumannii (CRAB) is recognized as one of the most threatening Gram-negative bacilli. H-NS is known to play a role in controlling the transcription of a variety of different genes, including those associated with the stress response, persistence, and virulence. In the present work, we uncovered a link between the role of H-NS in the A. baumannii stress response and its relationship with the envelope stress response and resistance to DNA-damaging agents. Overall, we posit a new role of H-NS, showing that H-NS serves to endure envelope stress and could also be a mechanism that alleviates the stress induced by MBL expression in A. baumannii. This could be an evolutionary advantage to further resist the action of carbapenems.
doi:10.1128/msphere.00793-20 pmid:32848010 fatcat:gg7joogbkrb2lm5fef4kv5dluy