TABLE 1.

Summary of analysis results of STEC strains isolated from produce

Strain	Serotypea	Source	Results of analysis
			PCRb	Stx2c	EhxAd	saae	subABf	sabg
09-00002	NA	Spinach	stx2, ehxA	+	+	+	+	NAh
09-00009	O172:H2	Spinach	stx2	−	NA	−	−	NA
09-00024	O116:H21	Spinach	stx2, ehxA	+	+	+	+	NA
09-00025	O116:H21	Spinachi	stx2, ehxA	+	+	+	+	NA
09-00026	O116:H21	Spinachi	stx2	+	NA	−	−	NA
09-00027	O113:H?	Spinach	stx2, ehxA	+	+	+	+	−
09-00028	O8:H−	Spinach	stx2, ehxA	−	Weak +	−	−	NA
09-00029	O11:H15	Spinach	stx2?	−	NA	−	−	NA
09-00031	O−:H19	Spinach	stx2, ehxA	+	+	+	+	NA
09-00039	O168:H8	Spinach	stx2, ehxA	+	−	−	−	NA
09-00043	O−:H21	Spinach	stx2	−	NA	−	−	NA
09-00047	O113:H21	Spinach	stx2, ehxA	+	+	+	+	−
09-00049	O168:H−	Lettuce	stx2, ehxA	+	−	−	−	NA

^aO and H serotyping results from the E. coli Reference Center, Penn State University.

^bVarious PCRs were used to test for stx₁ and stx₂, ehxA (enterohemolysin), γ-eae, and other eae alleles, and for O antigen genes for O157, O26, O111, O121, O145, and O103 serotypes.

^cSerological analysis was done to test for Stx2 using VTEC-RPLA (Denka Seiken, Japan).

^dEnterohemolysis was done on blood agar plates with Ca²⁺ to test for EhxA.

^ePCR was used to test for the Saa gene.

^fPCR was used to test for the subtilase cytotoxin genes.

^gPCR was used to test for the gene encoding the STEC autotransporter protein.

^hNA, not applicable.

ⁱOrganic product.