Table 1.

Genotypic and phenotypic characterization of S. aureus clinical isolates.

		QRDR mutationsb		MIC (mg/L)c
				EtBr			CIP			NOR			NAL
Isolatea	PFGE pattern	GrlA	GyrA	No	+	+	No	+	+	No	+	+	No	+	+
				EI	TZ	CPZ	EI	TZ	CPZ	EI	TZ	CPZ	EI	TZ	CPZ
ATCC25923	-	WT	WT	6.25	0.75	0.75	0.25	0.125	0.125	0.5	0.125	0.125	64	n.d.	n.d.
ATCC25923EtBr	-	WT	WT	200	25	12.5	1	0.25	0.25	2	0.25	0.25	64	n.d.	n.d.
SM1	A2	S80Y/E84K	S84L	16	4	4	128	32	64	512	128	256	256	64	64
SM10	A4	S80Y/E84K	S84L	16	2	4	128	64	64	512	128	128	128	64	64
SM14	A3	S80Y/E84K	S84L	16	4	4	256	32	128	1024	128	256	256	64	64
SM17	A4	S80Y/E84K	S84L	16	4	4	256	64	64	1024	256	512	256	64	64
SM25	A1	S80Y/E84K	S84L	8	2	4	128	32	64	512	64	128	256	32	64
SM27	A4	S80Y/E84K	S84L	16	4	4	256	32	64	512	128	256	256	64	64
SM43	A1	S80Y/E84K	S84L	16	2	4	128	64	64	512	128	128	512	256	64
SM46	A1	S80Y/E84K	S84L	16	4	4	128	64	64	512	128	256	128	64	64
SM47	A1	S80Y/E84K	S84L	8	2	4	256	32	64	512	128	256	256	64	64
SM48	A1	S80Y/E84K	S84L	8	4	4	256	32	64	512	128	256	256	64	64
SM50	B1	S80F/E84K	S84L	8	1	2	64	16	16	256	32	64	128	64	64
SM52	C1	E84K	S84L	16	1	2	16	8	8	64	32	32	128	32	64
SM2	B2	S80F/E84K	S84L	8	2	2	32	16	16	128	32	32	64	16	64
SM3	E1	S80Y/E84K	S84L	1	1	1	16	8	8	64	32	32	64	16	16
SM4	E2	S80F	S84L	4	2	1	8	8	8	64	32	32	64	32	64
SM5	E3	S80Y/E84K	S84L	4	2	1	32	16	16	128	64	64	64	32	32
SM6	A5	S80F	E88K	4	2	1	16	16	16	64	32	32	64	32	32
SM7	E1	S80F	S84L	2	2	1	8	8	4	64	32	32	128	32	64
SM8	A5	S80F	E88K	4	2	1	16	8	16	128	64	64	128	32	64
SM12	E1	S80F	S84L	2	2	1	16	8	8	64	32	32	128	32	64
SM16	A6	S80F	E88K	4	2	1	16	16	16	128	32	64	64	32	64
SM22	A1	S80Y/E84G	S84L	8	4	4	128	16	32	512	128	128	64	32	64
SM34	D1	S80F/E84K	S84L	4	2	2	64	16	32	64	16	32	32	16	32
SM36	E1	S80F	S84L	4	2	2	16	8	8	64	16	32	128	32	64
SM40	E1	S80F	S84L	8	4	4	32	32	32	512	128	128	16	8	16

^aIsolates in bold correspond to the EtBrCW-positive isolates. ^bWT: wild-type; S: serine; F: phenylalanine; E: glutamate; K: lysine; Y: tyrosine; L: leucine; G: glycine. ^cValues in bold-type correspond to a MIC decrease of ≥ four-fold in the presence of the efflux inhibitor (EI) in comparison to the values with no EI [10]. The concentration of each EI used is defined in the Methods section. EtBr: ethidium bromide; CIP: ciprofloxacin; NOR: norfloxacin; NAL: nalidixic acid; TZ: thioridazine; CPZ: chlorpromazine; n.d.: not determined.