TABLE 5.

Association of Φ2851 q, o, and ant genes with stx genes in wild-type E. coli O157:H7 strains

			No. of strains in:
stx gene	O157:H7 strains		q2851 gene PCR		02851 gene PCR		antB2851 gene PCR
	Total no.	Origin (no. of strains)a	Positive	Negative	Positive	Negative	Positive	Negative
Negative	8b	D (6), NL (2)	0	8	0	8	0	8
stx1	1	D (1)	1	0	1	0	1	0
stx2	24c	D (23), USA (1)	3	21	2	22	2	22
stx1 + stx2	14d	USA (9), CAN (3), UK (1), D (1)	0	14	1	13	1	13
stx2c	4e	D (4)	3	1	3	1	2	2
stx1 + stx2c	26f	D (25), USA (1)	26	0	24	2	3	23
stx2 + stx2c	5g	USA (1), DK (2), UK (1), D (1)	5	0	5	0	4	1
All	82		38	44	36	46	13	69

^aCountry of origin: D, Germany; NL, The Netherlands; UK, United Kingdom; DK, Denmark; USA, United States. CAN, Canada.

^bAll strains were negative for verotoxicity (verocell test) and for stx genes (PCR).

^cTwo strains from Germany were positive for q₂₈₅₁, O₂₈₅₁, and the ant_B2851 gene; one strain was positive only for the q₂₈₅₁ gene but negative for o₂₈₅₁ and ant_B2851.

^dOne strain from the United States was negative for q₂₈₅₁ but positive for o₂₈₅₁ and ant_B2851.

^eTwo strains were positive for q₂₈₅₁, o₂₈₅₁, and ant_B2851 genes; one was positive only for q₂₈₅₁ and o₂₈₅₁ genes; and another strain was negative for q₂₈₅₁, o₂₈₅₁, and ant_B2851 genes.

^fAll strains were positive for the q₂₈₅₁ gene. Among the German strains, the o gene was missing in 2 isolates and the ant_B2851 gene was missing in 23 isolates. The strain from the United States was positive for all q₂₈₅₁, o₂₈₅₁, and ant_B2851 genes.

^gAll strains were positive for q₂₈₅₁ and o₂₈₅₁ genes; the ant_B2851 gene was missing in the German isolate.