Carprofen-induced depletion of proton motive force reverses TetK-mediated doxycycline resistance in methicillin-resistant Staphylococcus pseudintermedius

Magnowska, Z; Jana, B; Brochmann, R P; Hesketh, A; Lametsch, R; De Gobba, C; Guardabassi, L

Abstract

We previously showed that doxycycline (DOX) and carprofen (CPF), a veterinary non-steroidal anti-inflammatory drug, have synergistic antimicrobial activity against methicillin-resistant Staphylococcus pseudintermedius (MRSP) carrying the tetracycline resistance determinant TetK. To elucidate the molecular mechanism of this synergy, we investigated the effects of the two drugs, individually and in combination, using a comprehensive approach including RNA sequencing, two-dimensional differential in-gel electrophoresis, macromolecule biosynthesis assays and fluorescence spectroscopy. Exposure of TetK-positive MRSP to CPF alone resulted in upregulation of pathways that generate ATP and NADH, and promote the proton gradient. We showed that CPF is a proton carrier that dissipates the electrochemical potential of the membrane. In the presence of both CPF and DOX, the energy compensation strategy was attenuated by downregulation of all the processes involved, such as citric acid cycle, oxidative phosphorylation and ATP-providing arginine deiminase pathway. Furthermore, protein biosynthesis inhibition increased from 20% under DOX exposure alone to 75% upon simultaneous exposure to CPF. We conclude that synergistic interaction of the drugs restores DOX susceptibility in MRSP by compromising proton-motive-force-dependent TetK-mediated efflux of the antibiotic. MRSP is unable to counterbalance CPF-mediated PMF depletion by cellular metabolic adaptations, resulting in intracellular accumulation of DOX and inhibition of protein biosynthesis.

Citation

Magnowska, Z., Jana, B., Brochmann, R. P., Hesketh, A., Lametsch, R., De Gobba, C., & Guardabassi, L. (2019). Carprofen-induced depletion of proton motive force reverses TetK-mediated doxycycline resistance in methicillin-resistant Staphylococcus pseudintermedius. https://doi.org/10.1038/s41598-019-54091-4

• Journal Article Type: Article
• Acceptance Date: Oct 31, 2019
• Publication Date: Nov 28, 2019
• Deposit Date: Dec 17, 2019
• Publicly Available Date: Dec 18, 2019
• Journal: Scientific Reports (Nature)
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1038/s41598-019-54091-4
• Public URL: https://rvc-repository.worktribe.com/output/1379533