Automated ribotyping and random amplified polymorphic DNA analysis for molecular typing of Salmonella enteritidis and Salmonella typhimurium strains isolated in Italy

Aims: The ability of automated ribotyping and random amplified polymorphic DNA (RAPD) analysis to differentiate Salmonella enteritidis and Salmonella typhimurium isolates in relation to their origin was evaluated. Methods and Results: The restriction enzymes EcoRI, PvuII and PstI, and the random primers OPB17 and P1254, were tested for ribotyping and RAPD analys is, respectively. Seventeen subtypes were identified among the isolates of the two pathogenic Salmonella serovars using the RiboPrinter(R), and 25 sub types using RAPD. Conclusions: The greatest degree of genetic diversity was observed among Sa lm. typhimurium isolates using both automated ribotyping (Simpson's index o f discrimination 0878) and RAPD (Simpson's index of discrimination 0886). Significance and Impact of the Study: According to the results of this rese arch, automated ribotyping and RAPD are two useful genotyping techniques fo r identifying unique and common subtypes associated with a specific source and location, and provide powerful tools for epidemiological investigations .