Molecular Typing of Salmonella Infantis Clinical Strains Isolated in Tehran

Document Type : Original Research

Authors

1 Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran

2 Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran

3 Health Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran

Abstract

Aims: Salmonella spp are among the most important food‑borne pathogens both in humans and animals. The purpose of this study was to investigate the molecular types of S. infantis strains isolated in Tehran, Iran.

Methods: Over a two year study, S. infantis strains isolated from various clinical samples in several hospitals of Tehran, were included in the study. Then, standard microbiological and serological methods were applied in order to identify isolated strains. Phenol‑chlorophorm technique also was used to extract bacterial DNA. The clonal relatedness between the isolated strains was studied by Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC‑ PCR).

Results: 40 isolated strains were identified as S. infantis which were further studied by ERIC‑PCR. This technique produced 4 to 11 DNA bands. Besides, it divided all S. infantis strains into 8 genotype groups (I1-I8). I1 genotype group was the most common cluster (47.5%).

Conclusion: The results of study suggest that S. infantis strains recovered from clinical cases in Tehran, had a large genetic diversity. We also found the ERIC‑PCR as a useful method for molecular typing of S. infantis isolated strains.

Keywords