Gallien P, Karch H, Much C, Steinrück H, Lehmann S, Timm M, Richter H, Perlberg KW, Protz D (2000): Subtyped eae-genes in Shigatoxin-produced Escherichia coli (STEC) - Occurrence in raw or undercooked food samples and comparison of isolates from faecal samples and stool samples
Fleischwirtschaft 80 (2): 84-89.

We subtyped eae-genes in 19 isolates from raw or undercooked samples (milk, meat, sausage, cheese) by using PCR. Furthermore we investigated 17 isolates from faecal samples from cattle and 30 isolates from stool samples from HUS-and enteritis patients and from carriers without symptoms for comparison. We detected the gamma-eae type first and foremost in 20 isolates belonging to serogroups O157:H7 or O157:H-.In addition it was found in 5 strains belonging to serogroup O145 and in 1 isolate of serogroup O111. beta-eae was detected in 7 isolates belonging to serogroup O26 and in 2 strains of serogroups O118 and O5. It was impossible to estimate the serogroup of 6 other isolates containing the beta-type. alpha-eae was detected in 5 isolates of different serogroups but the epsilon-type was found in 10 isolates belonging to serogroup O103:H2. It was impossible to detect differences in occurrence of eae-types between isolates from foods, faeces or stool samples. Furthermore we used different PCR systems for investigation of the insertion of locus of enterocyte effacement (LEE) in sel C. We detected that a LEE, containing the epsilon-eae is not integrated in sel C. But a LEE with the alpha-eae disruptes the sel C. All isolates containing the gamma-type showed only a positive PCR result by using primer pair K295/K296 indicating an insertion in sel C. But PCR results by using primer pair K255/K260 were negative. All beta-eae containing strains showed no PCR signal independent of the primer types. Further investigations by using DNA-Sequencing are necessary for detection of other LEE-insertion loci like phe U.