Table 1.

Trimethoprim, sulfamethoxazole, and trimethoprim-sulfamethoxazole susceptibilities of selected clinical and environmental isolates with and without the BpeEF-OprC efflux pump^a

Strain	MIC (μg/ml)
	SXT (bpeE+F+-oprC+)	SMX (bpeE+F+-oprC+)	TMP
			bpeE+F+-oprC+	Δ(bpeEF-oprC)	Δ(bpeEF-oprC), complemented,b uninduced	Δ(bpeEF-oprC), complemented,b +1 mM IPTG
1026b	0.094/1.79	4	0.75	0.5	0.5	6
Thailand Clinical
2650a	1/19	8	≥32	1.5	1.5	≥32
2665a	1/19	16	≥32	1.5	1.5	16
2677a	1.5/28.5	24	≥32	2	2	≥32
2719a	1/19	12	≥32	1	1	16
2769a	0.75/14.25	12	16	1.5	2	≥32
Thailand environmental
E0016	0.75/14.25	12	≥32	1	1.5	16
E0235	1.5/28.5	24	≥32	1.5	3	≥32
E0237	0.5/9.5	8	4	1	2	16
E0342	0.75/14.25	24	≥32	1	1.5	16
Australia clinical
MSHR305	0.5/9.5	32	≥32	2	2	16
MSHR668	0.38/7.22	16	≥32	2	2	32
MSHR465a	1/19	32	≥32	3	2	≥32

^aAbbreviations: TMP, trimethoprim; SMX, sulfamethoxazole; SXT, trimethoprim-sulfamethoxazole.

^bThe respective strains containing the Δ(bpeEF-oprC) mutation have a mini-Tn7T-P_tac-bpeE⁺F⁺-oprC⁺ element integrated at the chromosomal glmS2 locus, except for the MSHR668 derivative, which has the same element integrated at glmS3. The bpeE⁺F⁺-oprC⁺ operon contained on this mini-Tn7 element is derived from prototype strain 1026b (18).