Metabolic control of drug resistance by a mycobacterial ion channel

Gouzy, A.; Li, S.; Chen, J.; Na, A.; Saleh, A.; Azadian, Z. A.; Tam, K.; Munsamy-Govender, V.; Poulton, N. C.; DeJesus, M. A.; Schnappinger, D.; Rhee, K. Y.; Ehrt, S.; Rock, J. M.

doi:10.64898/2026.03.10.710584

bioRxiv · 10.64898/2026.03.10.710584

Metabolic control of drug resistance by a mycobacterial ion channel

Gouzy, A.·Li, S.·Chen, J.·Na, A.·Saleh, A.·Azadian, Z. A.·Tam, K.·Munsamy-Govender, V.·Poulton, N. C.·DeJesus, M. A.·Schnappinger, D.·Rhee, K. Y.·Ehrt, S.·Rock, J. M.

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Abstract

Pyrazinamide (PZA) is a cornerstone of modern tuberculosis therapy, yet its context-dependent activity has obscured both its mode of action and resistance mechanisms. Using a host-mimicking culture system integrated with genome-wide CRISPRi profiling, metabolomics, and comparative genomics, we identify a previously unrecognized driver of PZA resistance in humans: loss of the ion channel Rv2571c. Rv2571c mediates -ketoglutarate efflux, amplifying PZA-induced cytoplasmic acidification under host-relevant acidic conditions. Loss-of-function mutations confer resistance in vitro and in vivo and are under positive selection in clinical isolates, establishing this pathway as a resistance determinant in patients. Together, these findings define a novel, ion channel-mediated resistance mechanism, establish cytoplasmic acidification as the basis of PZA killing, and inform resistance detection and treatment-shortening drug development.

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Gouzy, A., Li, S., Chen, J., Na, A., Saleh, A., Azadian, Z. A., Tam, K., Munsamy-Govender, V., Poulton, N. C., DeJesus, M. A., Schnappinger, D., Rhee, K. Y., Ehrt, S., Rock, J. M.. 2026-03-10. Metabolic control of drug resistance by a mycobacterial ion channel. https://doi.org/10.64898/2026.03.10.710584

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