Pulsed-field gel electrophoresis typing of enteroaggregative Escherichia coli isolates

Objective To understand the molecular epidemiological characteristics of enteroaggregative Escherichia coli (EAEC) isolates from sporadic diarrheal patients in China and establish related database. Methods Pulsed-field gel electrophoresis (PFGE) was performed according to the PulseNet protocol of Escherichia coli O157:H7 with minor modifications. An UPGMA dendrogram was constructed with BioNumerics software. Results According to the PulseNet protocol, 48 PFGE patterns were obtained from 52 EAEC isolates, and then they were divided into 14 groups named from A to N. Isolates from different regions or isolates with different adherent phenotypes to HEp-2 cells were widely distributed in different groups. Conclusion The EAEC isolates from sporadic diarrheal patients in China were highly polymorphic. The PFGE protocol developed in this study seemed to be suitable for the molecular typing of EAEC isolates in China.