. 2009 Jan 26;53(4):1367–1376. doi: 10.1128/AAC.01275-08

TABLE 2.

Drug susceptibilities of M. smegmatis isolates transformed with different erm(41) alleles^a

Donor M. abscessus isolate(s)^b	Donor phenotype	Preincubation (20-24 h)		MIC (μg/ml)
Donor M. abscessus isolate(s)^b	Donor phenotype	Agent	Concn (μg/ml)	ERY	CLR	CLN	Q	TEL
MC879, MC958, MC719, MC720	Inducibly resistant	None		32	2	64	128	8
		ERY	2	>128	16	>512	128	>128
MC879-2	Resistant^c	None		32	2	ND	ND	ND
		ERY	2	>128	16	ND	ND	ND
MAB30, MC1028, MC1082	Susceptible	None		4	≤0.5	32	128	4
		ERY	2	4	≤0.5	32	128	4
Vector control	NA	None		4	≤0.5	ND	ND	ND
		ERY	2	4	≤0.5	ND	ND	ND

ERY, erythromycin; CLR, clarithromycin; CLN, clindamycin; Q, quinupristin; TEL, telithromycin; NA, not applicable; ND, not determined. CLN, Q, and TEL were tested only against M. smegmatis isolates transformed with erm(41) alleles derived from M. abscessus isolates MC879 and MC1028.

Source of the erm(41) allele.

The donor M. abscessus isolate MC879-2 had an A2058→C 23S rRNA gene mutation and was constitutively resistant to clarithromycin (MIC > 32 μg/ml).