TABLE 4.

Alterations in GyrA, ParC, and ParE genes observed in isolates of S. pneumoniae demonstrating reduced susceptibility to fluoroquinolones

Strain	Mutation(s)a in QRDR of:					MIC (μg/ml)b
	GyrA	ParC			ParE	OFLX	LEVO	SPAR	GREP	TROV	CLFX
ATCC 49619	Ser-81	Ser-79	Ser-80	Asp-83	Asp-435	2	1	0.5	0.25	≤0.12	≤0.12
R6	—	—	—	—	—	2	1	0.25	0.25	≤0.12	≤0.12
TN4201	—	Phe	—	—	—	8	4	1	1	1	0.25
TN3659-6	—	Phe	—	—	—	8	4	2	2	1	0.25
F30078	—	Tyr	—	—	—	8	4	2	2	0.5	0.25
F31324	Phe	—	—	—	Asn	16	8	2	2	0.5	0.5
F30084	Phe	—	—	—	Asn	>16	8	2	2	0.5	1
J3810	Phe	—	Pro	Tyr	—	>16	16	16	8	8	0.5
MD3904	Phe	Phe	—	—	—	>16	16	16	8	8	0.5
CT5-5821	Phe	Phe	—	—	—	>16	16	16	8	8	0.5

^aGyrA, ParC, and ParE amino acid positions are based on the respective gene sequences for S. pneumoniae (1, 24). —, no difference from S. pneumoniae 49619. 

^bOFLX, ofloxacin; LEVO, levofloxacin; GREP, grepafloxacin; SPAR, sparfloxacin; TROV, trovafloxacin; CLFX, clinafloxacin.