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bioRxiv · 10.1101/2021.08.18.456922

Impact of Human Serum Proteins on Susceptibility of Acinetobacter baumannii to Cefiderocol: role of iron transport

Le, C.·Pimentel, C.·Pasteran, F.·Tuttobene, M. R.·Subils, T.·Escalante, J.·Nishimura, B.·Arriaga, S.·Carranza, A.·Vila, A. J.·Corso, A.·Actis, L. A.·Tolmasky, M.·Bonomo, R. A.·Ramirez, M. S.
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Abstract

Cefiderocol is a siderophore antibiotic that co-opts iron transporters to facilitate cell entry. We show that genes related to iron uptake systems and resistance to {beta}-lactams in Acinetobacter baumannii have altered expression levels in the presence of human serum, human serum albumin, or human pleural fluid. Cefiderocol MICs are also raised in the presence of the mentioned fluids. Clinical response in A. baumannii infections may be related to the interplay of these human factors.

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Le, C., Pimentel, C., Pasteran, F., Tuttobene, M. R., Subils, T., Escalante, J., Nishimura, B., Arriaga, S., Carranza, A., Vila, A. J., Corso, A., Actis, L. A., Tolmasky, M., Bonomo, R. A., Ramirez, M. S.. 2021-08-19. Impact of Human Serum Proteins on Susceptibility of Acinetobacter baumannii to Cefiderocol: role of iron transport. https://doi.org/10.1101/2021.08.18.456922

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