A multiplex PCR for detection of enterotoxin genes in Aeromonas species isolated from foods of animal origin and human diarrhoeal samples

AimsThe present study describes incidence and enterotoxin gene profile of Aeromonas spp. from human diarrhoeal samples (83) and raw meats (171). Methods and ResultsThe samples were screened for isolation of Aeromonads. Aeromonas spp. contaminated raw meats of all kinds under the study and per cent contamination in chicken, mutton and beef was 1403, 2289 and 1935, respectively. Of the 83 diarrhoeal samples from children, 6 (722%) were positive for presence of Aeromonas spp. Seven different species of Aeromonas (Aer.hydrophila, Aer.caviae, Aer.veronii bv sobria, Aer.trota, Aer.schubertii, Aer.jandaei and Aer.allosaccharophila) could be identified from foods and from diarrhoeal samples two species (Aer.caviae and Aer.hydrophila) were encountered. Unique primers were designed, and a multiplex PCR was standardized for detection of three enterotoxin genes (act, alt, ast) in the Aeromonas spp. Of the 39 isolates, 35 (8974%) carried one or more enterotoxin genes: act, alt and ast genes were detected in 30 (7692%), 31 (7948%) and 4 (1025%) isolates, respectively. The enterotoxin genes from a strain recovered from mutton were sequenced and submitted to GenBank and the accession no.s KC687135, KC633828 and KC687134 were provided for alt, ast and act, respectively, by the GenBank. ConclusionsThe occurrence of enterotoxigenic Aeromonads in raw meats and diarrhoeal samples is a public health concern. Significance and Impact of the StudyGiven the increasing evidence of involvement of Aeromonads in foodborne outbreaks, the standardization of single-step multiplex PCR will be helpful tool for detection of enterotoxin genes in Aeromonas spp.