Table 1. Activity of moxifloxacin and delafloxacin alone or combined with caspofungin against planktonic bacteria and 24- h-biofilms.
| Strain* | MIC† (mg l−1) | Fluoroquinolone concentrations (mg l−1) needed to reduce bacterial viability in biofilms of 50%‡ | |||||
|---|---|---|---|---|---|---|---|
| MXF† | DFX† | CAS† | MXF |
DFX |
|||
| Alone | +CAS§ | Alone | +CAS§ | ||||
| ATCC33591 (MRSA) | 0.032 | 0.004 | 80 | 1.25 | 0.1 | 0.125 | 0.125 |
| 2011S027 (MSSA) | 0.125 | 0.004 | 80 | 0.9 | 0.7 | 0.5 | 0.125 |
| Surv2003/1083 (MSSA) | 0.125 | 0.004 | 160 | >20|| | 17 | >20|| | 2 |
| 2009S025 (MRSA) | 0.125 | 0.125 | 80 | >20 | 1.9 | 4 | 1 |
| Surv2005/104 (MRSA) | 2 | 0.125 | 160 | >20 | 18 | >20 | 2 |
| Surv2005/179 (MRSA) | 2 | 0.016 | 80 | >20 | 3.8 | >20 | 4 |
| 2009S028 (MRSA) | 2 | 0.016 | 80 | >20 | 3.7 | 8 | 0.5 |
| Surv2003/651 (MRSA) | 2 | 0.125 | 160 | >20 | >20 | >20 | 8 |
| Xen36 (MSSA) (bioluminescent strain derived from S. aureus ATCC 49525) | 1 | 0.016 | 80 | >20 | 10.4 | >20 | 1 |
*All clinical isolates belong to the epidemic CC5 or CC8 clonal complexes; see Siala et al.30 for origin and description; MSSA, methicillin susceptible S. aureus; MRSA, methicillin-resistant S. aureus.
†MIC, minimal inhibitory concentration; MXF, moxifloxacin; DFX, delafloxacin; CAS, caspofungin.
‡Calculated using the Hill function fitted to the data of concentration–response experiments similar to those presented in Supplementary Fig. 3 for selected strains.
§Used at 40 mg l−1.
||Effect not reached at 20 mg l−1.