SERE, A WIDELY DISPERSED BACTERIAL REPETITIVE DNA ELEMENT

The presence of a Salmonella serotype Enteritidis repeat element (SERE ) located within the upstream regulatory region of the sefABCD operon encoding fimbrial proteins is reported. DNA dot-blot hybridisation ana lyses and computerised searches of genetic databases indicate that SER E is well conserved and widely distributed throughout the bacterial an d archaeal kingdoms. A SERE-based polymerase chain reaction (SERE-PCR) assay was developed to fingerprint 54 isolates of Enteritidis represe nting nine distinct phage types and 54 isolates of other Salmonella se rotypes. SERE-PCR identified five distinct fingerprint profiles among the 54 Enteritidis isolates; no correlation between phage types and SE RE-PCR fingerprint patterns was noticed. SERE-PCR was reproducible, ra pid and easy to perform. The results of this investigation suggest tha t the limited heterogeneity of SERE-PCR fingerprint patterns can be ut ilised to develop serotype-and serogroup-specific fingerprint patterns for isolates of Enteritidis.