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A. We-thank-anne-davin-regli, M. Masi, R. Stavenger, J. Bolla, A. Tran et al., Coumarinceftazidime and 6-MeOQ-ceftazidime were prepared for research purposes only and not for clinical use. The research leading to these results was conducted as part of the TRANSLOCATION consortium and has received support from the Innovative Medicines Initiatives Joint Undertaking under Grant Agreement n°115525, resources which are composed of financial contribution from the European Union's seventh framework program (FP7/2007-2013) and EFPIA companies in kind contribution. This work was also supported by CNRS, and Service de Santé des Armées, and by Soleil program, 20130949.