TABLE 2.

Fluoroquinolone susceptibilities of S. pneumoniae C3LN4, first-step mutants, and clinical isolates

Strain	Fluoroquinolone MIC (μg/ml)a
	LVFX	OFLX	CPFX	SPFX	STFX
C3LN4	0.1	0.3	0.2	0.15	0.005
SPFX1b	0.1	0.3	0.2	0.4	0.005
CPFX1c	0.1	0.3	0.5	0.15	0.005
OFLX1d	0.3	0.75	0.6	0.8	0.005
JP17e	6.25	12.5	6.25	1.56	0.39
JP27e	25	50	50	25	0.39

^aLVFX, levofloxacin; OFLX, ofloxacin; CPFX, ciprofloxacin; SPFX, sparfloxacin; STFX, sitafloxacin. Those MICs greater than those for the wild type are shown in boldface type. 

^bSelected with sparfloxacin (the MICs for the other five mutants were identical). 

^cSelected with ciprofloxacin (MICs for the other 11 mutants were identical). 

^dSelected with ofloxacin. 

^eClinical isolates.