CHARACTERIZATION OF DIARRHOEAGENIC ESCHERICHIA-COLI CLONES BY RIBOTYPING AND ERIC-PCR

The ability of ribotyping and enterobacterial repetitive intergenic co ncensus-polymerase chain reaction (ERIC-PCR) to discriminate diarrhoea genic Escherichia coli clones of 122 strains belonging to 26 distinct serotypes was evaluated. The 26 serotypes corresponded to 24 ribotypes and 25 ERIC-types. Correlation between multilocus enzyme electrophore sis, ERIC-PCR and ribotyping was c. 90% for the dominant ribotypes. Re lated clones such as O55:H7 and O157:H7 presented similar ribotypes an d clustered together in a dendrogram, and the two divergent clonal gro ups of enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC) were included in distinct branches. The results suggest the pos sibility of applying these two simpler techniques as tools to identify clones of diarrhoeagenic E. coli.