TABLE 1.

Strains used in this study

Organism	Reference or source	stx1f	yehVg	stx2f	wrbAg
STEC 1 lineage
O55:H7
TB156A, TB182Aa,b	6	−	I	−	I
5A, 5B, 5C, 5D	4
5Ec	4	−	O	−	I
O157:H7
84-01,a,b 87-01, 87-20a,b	43	+	O	+	O
93-111	3
EK3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 20, 21, 22, 24, 25, 26	26
U3, 4, 9, 10, 12, 13, 14, 15, 19, 21, 22, 34, 26, 28, 30, 31, 34, 35, 36, 40, 41, 43, 44, 46, 47, 48, 49, 50, P1, 4, 6, 9, 10, H2	8
86-24,d 86-28,d 86-17,e 87-07e	43	−	O	+	O
EK15, 28	26
U39	8
87-14	43	−	O	+	I
EK1,b 2, 18,b 19,b 23, 27	26
U2, 5, 7, 11, 16, 17, 18, 20, 24, 29, 32, 33, 42, 45,d 51, 52, P3, 7, H4, 5	8
P8	8	−	I	+	O
Sorbitol-fermenting O157:H−
CB2755b	Lothar Beutin	−	I	+	O
493/89	13
Non-STEC 1 lineage
Non-O157:H7
TB352A (O26:NM), TB334C (O85:NM), TB285A (O126:H2), TB154A (O103:H6)	6	+	I	−	I
EK30, 31, 32, 33 (O103:H2), EK34 (O111:nonmotile), EK35 (O111:H8), EK36, 37 (O118:H16), EK39 (Orough:H11)	26
EK38 (O121:H19)	26	−	I	+	I
TB226A (O111:HN)	6	+	I	+	I

^aAmplicons in yehV in this strain have been sequenced.

^bAmplicons in wrbA in this strain have been sequenced.

^cLeft end of bacteriophage occupies yehV; right end of bacteriophage not detected at this junction.

^dStrain has Δ20,214 bacteriophage.

^eStrain has Δ18,895 bacteriophage.

^f+, present; −, absent.

^gI, intact; O, occupied.