Table 3.

Distribution of PMQR genes and mutations in gyrA, gyrB, parC, and parE genes in S. Typhimurium isolates with decreased susceptibility to ciprofloxacin in Shanghai, China.

QRDR mutation				PMQR	N		Total
gyrA	gyrB	parC	parE		I∗	R∗∗
WT	WT	WT	WT	qnrS	1	0	1
WT	WT	WT	WT	aac(6′)-Ib-cr	1	0	1
WT	WT	WT	WT	aac(6′)-Ib-cr,qnrB	1	3	4
D87Y	WT	WT	WT	WT	15	0	15
D87Y	WT	WT	WT	aac(6′)-Ib-cr	20	4	24
D87N	WT	WT	WT	aac(6′)-Ib-cr	13	4	17
D87Y	WT	WT	WT	aac(6′)-Ib-cr,qnrB	0	2	2
S83F/D87N	WT	S80R	WT	WT	0	4	4
S83F/D87N	WT	S80R	WT	aac(6′)-Ib-cr	0	1	1
S83F/D87G	WT	S80R	WT	WT	0	1	1
S83F/D87N	WT	T57S/S80R	WT	aac(6′)-Ib-cr	0	1	1

^∗S. Typhimurium isolates with intermediate resistance to CIP (MIC = 2 μg/mL); ^∗∗S. Typhimurium isolates with resistance to CIP (MIC ≥ 4 μg/mL); WT, wild type.