TABLE 2.

Distribution of tetQ and of MLS- and CTnDOT-specific genes found in community and clinical Bacteroides sp. isolates

Isolate groupc (n)	% of isolates with resistance or hybridizing to the indicated probe
	Tcr	CTnDOT element probesa				Emr	MLS and IS probesb
		tetQ	CTn ends	rteB	rteC		ermF	ermG	ermB	IS4351d
Community
VPI, pre-1970 (32)	28	28	34	47	31	0	0	0	0	0
VPI, 1970–1980 (33)	42	42	48	48	42	0	0	0	0	0
WH, 1996–1997 (86)	80	83	81	83	76	29	15	0	2	5
Sewage, 1997 (16)	62	62	88	81	75	38	12	6	6	0
Clinical
VPI, pre-1970 (23)	22	22	30	43	26	9	9	0	0	0
Loyola VA (65)	83	83	85	83	80	31	17	8	2	3
WAL Cm (20)	NDe	60	60	90	60	5	5	0	0	0
WAL Tc (14)	100	100	86	93	79	64	50	14	14	0
Other (10)	80	80	90	90	80	70	60	10	0	20

^aGenes found on a family of Bacteroides 50- to 70-kbp CTn's called the CTnDOT family (38). The sources of the DNAs used for probes are described in Table 1. 

^bMLS genes or erm genes found by hybridization. Active genes confer resistance to all three groups of antibiotics. Several strains hybridized to two different erm probes. 

^cStrains are described in Materials and Methods. Cm^r, all strains in this group were chloramphenicol resistant. Only two other strains, one community isolate and one clinical isolate, were found to be chloramphenicol resistant. Tc^r, all the strains in this group were tetracycline resistant. 

^dIS4351 has usually been found associated with Bacteroides regular compound transposons that also contain ermF. All of the IS4351-containing strains also hybridized to the ermF probe. 

^eND, not done.