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WGS of Staphylococcus aureus:  Gentamicin resistance - MIC 2-4ug/ml - Isolate 39
Mutants  resistant to the TO-GEN combination were generated by serial passage of S. aureus ATCC 29213 (30 passages  of 48 h each) in a series of 2-fold dilutions of GEN (range, 0.06 to 64  g/ml) in the presence of a fixed concentration of TO (8 g/ml) in brain  heart infusion (BHI) broth in 96-well plates. At each passage, the MIC was  determined as the minimal concentration of the antibiotic combination  inhibiting visible growth, and the well representing 0.5MIC was diluted in  fresh broth and used to inoculate (~106 CFU/ml) a new series of TO (8 g/ml)-GEN dilutions for the next  passage. At each passage, an aliquot of the 0.5MIC well was also spread on  BHI agar (BHIA), and the next day, three individual colonies were collected  and frozen. Similar passages and isolate selection were also performed in  parallel using GEN alone as the selective pressure. The whole genome of  isolates showing an increased resistance to the TO-GEN combination or to GEN  alone (three per passage of interest).
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SUB7033879
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