TABLE 2.

Amino acid changes encoded by mutations in the gyrA and parC gene loci and corresponding fluoroquinolone MICs (mg/liter^a)

Mutant in locus		n	Antibiotic	No. of isolates for which corresponding MICs were
gyrA	parC			≤0.06	012	0.25	0.5	1	2	4	8	16	32	≥64
—	—	29	Ciprofloxacin			1	6	14	7	1
			Levofloxacin			1	6	17	5
			Gatifloxacin	1	3	19	6
			Sparfloxacin	1	10	9	7	2
			Trovafloxacin	5	17	6	1
			Grepafloxacin	3	17	7	2
			Moxifloxacin	2	17	8	2
			Clinafloxacin	18	11
			Sitafloxacin	24	5
—	Arg-95→Cys	2	Ciprofloxacin				1		1
			Levofloxacin				1	1
			Gatifloxacin				2
			Sparfloxacin			1	1
			Trovafloxacin		1	1
			Grepafloxacin		1	1
			Moxifloxacin		2
			Clinafloxacin	1	1
			Sitafloxacin	2
—	Lys-137→Asn	6	Ciprofloxacin				1	3	2
			Levofloxacin				4	2
			Gatifloxacin			6
			Sparfloxacin		2	4
			Trovafloxacin	1	5
			Grepafloxacin		6
			Moxifloxacin		6
			Clinafloxacin	3	3
			Sitafloxacin	6
—	Ser-79→Phe	2	Ciprofloxacin						1	1
			Levofloxacin					1	1
			Gatifloxacin				1	1
			Sparfloxacin					1	1
			Trovafloxacin				1	1
			Grepafloxacin				1	1
			Moxifloxacin			2
			Clinafloxacin		2
			Sitafloxacin	2
Ser-81→Phe	—	2	Ciprofloxacin								1	1
			Levofloxacin							1	1
			Gatifloxacin						1	1
			Sparfloxacin						1	1
			Trovafloxacin						1	1
			Grepafloxacin						1	1
			Moxifloxacin					1	1
			Clinafloxacin			1	1
			Sitafloxacin			2
Ser-81→Tyr	—	3	Ciprofloxacin						1	1	1
			Levofloxacin							3
			Gatifloxacin				1	1	1
			Sparfloxacin					2	1
			Trovafloxacin			1	2
			Grepafloxacin			1	2
			Moxifloxacin		1	2
			Clinafloxacin		1	2
			Sitafloxacin	1	2	2
Ser-81→Phe	Asp-78→Asn	1	Ciprofloxacin							1
			Levofloxacin							1
			Gatifloxacin						1
			Sparfloxacin						1
			Trovafloxacin					1
			Grepafloxacin					1
			Moxifloxacin					1
			Clinafloxacin			1
			Sitafloxacin		1
Ser-81→Phe	Ser-79→Phe	16	Ciprofloxacin								4	6	3	3
			Levofloxacin							8	4	4
			Gatifloxacin						3	8	5
			Sparfloxacin					2	4	6	4
			Trovafloxacin				1	3	6	6
			Grepafloxacin					4	6	6
			Moxifloxacin					5	9	2
			Clinafloxacin			8	7	1
			Sitafloxacin		8	8
Ser-81→Phe	Ser-79→Phe	4	Ciprofloxacin								2	2
	Lys-137→Asn		Levofloxacin								2	2
			Gatifloxacin								2	2
			Sparfloxacin							1	3
			Trovafloxacin							2	2
			Grepafloxacin						1	1	2
			Moxifloxacin						3	1
			Clinafloxacin			1	2	1
			Sitafloxacin		2	1	1
Ser-81→Phe	Lys-137→Asn	2	Ciprofloxacin							2
	Asp-83→Asn		Levofloxacin							2
			Gatifloxacin						2
			Sparfloxacin						2
			Trovafloxacin				1	1
			Grepafloxacin					1	1
			Moxifloxacin				1	1
			Clinafloxacin			2
			Sitafloxacin		1	1
Ser-81→Phe	Asp-78→Asn	1	Ciprofloxacin							1
	Arg-95→Cys		Levofloxacin							1
			Gatifloxacin						1
			Sparfloxacin						1
			Trovafloxacin					1
			Grepafloxacin					1
			Moxifloxacin					1
			Clinafloxacin			1
			Sitafloxacin		1
Ser-81→Phe	Asp-78→Asn	1	Ciprofloxacin									1
	Lys-137→Asn		Levofloxacin								1
			Gatifloxacin							1
			Sparfloxacin							1
			Trovafloxacin						1
			Grepafloxacin						1
			Moxifloxacin						1
			Clinafloxacin				1
			Sitafloxacin			1

^aA dash (—) denotes a wild-type sequence with no mutations identified. Position numbers are based on the gyrA (3) and parC (18, 20) sequence of S. pneumoniae.