Differentiation of Salmonella typhimurium from gram-negative intestinal microbes by randomly amplified polymorphic DNA (RAPD) fingerprinting

In order to rapidly identify and differentiate Salmonella typhimurium from the intestinal gram-negative bacteria, randomly amplified polymorphic DNA (RAPD) fingerprinting of Salmonella typhimurium was carried out using random primers designated OPA-13 (5′-CAGCACCCAC-3′), OPB-10 (5′-CGTCTGGGAC-3′), OPB-18 (5′-CCACAGCAGT-3′), and OPJ-10 (5′-AAGCCCGAGG-3′), and its patterns compared with 6 representive intestinal, gram-negative bacterial strains, Vibrio parahaemolyticus, V. vulnificus, Enterobacter cloacae, Escherichia coli O157:H7, Pseudomonas aeruginosa, and Proteus sp., which are often found in foods. S. typhimurium had unique and distinct fingerprinting patterns. RAPD fingerprinting is thus concluded to be a rapid and sensitive method for the identification of S. typhimurium compared to conventional culturing procedures or immunoassays.