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bioRxiv · 10.1101/2024.10.18.619101

Determination of Pseudomonas aeruginosa MexXY-OprM specificity in a major efflux knockout system reveals distinct antibiotic substrate classes

Kavanaugh, L. G.·Hariharan, S. M.·Conn, G. L.
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Abstract

Defining the substrates of Resistance-Nodulation-Division (RND) systems is often complicated by the presence of multiple systems in a single bacterial species. Using a major efflux knockout strain, we developed a Pseudomonas aeruginosa system that enables controlled expression of MexXY-OprM in the absence of background efflux complexes with overlapping substrate profiles. This system identified three groups of potential substrates: substrates, partial substrates, and nonsubstrates, and defined trimethoprim as a new substrate for MexXY-OprM.

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Kavanaugh, L. G., Hariharan, S. M., Conn, G. L.. 2024-10-19. Determination of Pseudomonas aeruginosa MexXY-OprM specificity in a major efflux knockout system reveals distinct antibiotic substrate classes. https://doi.org/10.1101/2024.10.18.619101

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