Evaluation of ERIC-PCR method for determining genetic diversity among Escherichia coli isolated from human and retail imported frozen shrimp and beef

Abstract

There is a global concern and increasing reports regarding foodborne disease infections associated with consuming contaminated vegetables, seafood, meat, and poultry products. Among foodborne bacterial pathogens globally, Salmonella, Escherichia coli, and Shigella were the most frequently implicated in causing food poisoning infections in children and adults. In Saudi Arabia, the consumption rates of imported fresh fruits, vegetables, seafood, and meat products are considered high. Therefore, the development of simple PCR based DNA fingerprinting methods is essential to track the source and route of microbial contamination among imported frozen meat and seafood products. A total of 38 E. coli strains were subtyped using ERIC1R, ERIC2, and a pair combination (ERIC1R + ERIC2) to generate genomic fingerprinting. The three Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction (ERIC-PCR)-based primers were generated in 26, 24, and 16 different genotypes while using ERIC1R, ERIC2, and ERIC1R + ERIC2, respectively. The Discrimination Index values obtained by ERIC1R, ERIC2, and ERIC1R + ERIC2 were 0.976, 0.965, and 0.903, respectively. ERIC1R and ERIC2 primers had the best discriminatory ability and typeability value and proved suitable for investigating genetic analysis among the population of E. coli strains. At the same time, the ERIC1R + ERIC2 primer pair has average discriminatory power and typeability value for differentiating E. coli strains. These results suggest that subtyping using ERIC1R and ERIC2 primer is a more reliable and rapid typing strategy for E. coli strains.