TABLE 2.

QRDR amino acid substitutions and associated MICs of seven fluoroquinolones for clinical isolates of P. mirabilis

Strain	Amino acid at indicated positionb						MIC (μg/ml) ofa:
	GyrA		GyrB		ParC		CIP	LVX	CLX	GAT	MXF	TVA	GMX
	83	87	464	466	78	80
ATCC 29906	S	E	S	E	G	S	≤0.12	≤0.12	≤0.03	≤0.12	≤0.25	≤0.12	≤0.06
3201	—c	—	—	—	—	—	≤0.12	≤0.12	≤0.03	≤0.25	≤0.25	≤0.12	0.12
3154	—	—	F	—	—	—	≤0.12	≤0.12	≤0.03	0.5	0.5	0.25	0.12
1075	R	—	—	—	—	R	0.5	1	0.25	2	2	2	1
1549	I	—	—	—	—	I	1	1	0.25	2	8	16	4
3073	I	—	—	—	—	I	1	1	0.25	4	8	16	4
3523	I	—	—	—	—	R	1	1	0.25	4	8	16	4
1391	R	—	—	—	—	R	1	1	0.5	4	8	8	4
1411	R	—	—	—	—	R	1	2	0.5	4	8	8	4
1977	I	—	—	—	—	I	2	2	0.5	4	16	32	16
3917	I	—	—	—	—	R	4	4	0.5	8	8	8	8
1964	I	—	—	D	—	I	4	4	1	16	16	32	8
3110	R	—	F	—	—	I	4	4	1	16	16	32	8
1970	I	—	—	D	—	I	4	4	1	16	32	128	8
3087	I	—	—	—	—	I	8	2	0.5	4	8	16	16
5520	I	—	—d	—	—	I	8	2	1	8	8	16	16
1283	R	—	—	—	—	R	8	4	1	16	16	16	32
4045	—	K	—	—	—	R	8	4	2	8	8	4	8
3623	R	—	—	—	—	R	8	8	2	8	16	16	8
1223	R	—	Y	—	—	I	8	8	2	16	32	32	8
3116	R	—	—	—	—	R	8	8	2	16	64	64	32
1487	R	—	—	—	—	R	8	16	2	16	64	64	16
5662	R	—	—	—	—	R	16	4	1	8	8	4	8
3799	R	—	Y	—	—	I	16	4	2	16	16	16	8
5596	R	—	F	—	D	—	16	8	1	16	16	32	8
3790	R	—	Y	—	—	I	16	8	2	16	16	16	32
4069	R	—	Y	—	—	I	32	16	4	64	64	>128	32
3951	I	—	Y	—	—	R	128	32	4	64	32	32	>32
3750	R	—	F	—	—	I	128	64	8	128	128	64	32
3991	R	—	Y	—	—	I	>128	32	8	128	64	>128	>32

^aAbbreviations: CIP, ciprofloxacin; CLX, clinafloxacin; GAT, gatifloxacin; GMX, gemifloxacin; LVX, levofloxacin; MXF, moxifloxacin; TVA, trovafloxacin. NCCLS breakpoints (susceptible, intermediate, resistant) are as follows: CIP, 1, 2, and 4 μg/ml, respectively; LVX, 2, 4, and 8 μg/ml, respectively. No breakpoints are available for CLX, GAT, MXF, TVA, or GMX.

^bAmino acid positions numbered according to E. coli gyrA, gyrB, and parC sequences (10, 19, 24).

^c—, no change from type strain sequence.

^dStrain 5520 has a 3-nucleotide insert (AAG, encoding an additional lysine) in gyrB, between the codons for K455 and A456.