Identification of Genes Responsible for Pathogenicity in a Diarrhea-causing Strain of Escherichia coli Pathovars Clinically Isolated Specimens by Multiplex PCR

Document Type : Original Article


1 Msc in Microbiology.Department of Microbiology, Saveh Branch, Islamic Azad University, Saveh, Iran.

2 Assistant Professor of Microbiology. Department of Microbiology, Saveh Branch, Islamic Azad University, Saveh, Iran.


Background and Objectives: Escherichia coli causes intestinal and extra intestinal diseases and is a major cause of diarrhea in children in developing countries. The aim of this study was to determine the molecular identity of pathogenic E.coli isolated from clinical samples by the Multiplex PCR.
Subjects and Methods: In this cross-sectional study 150 stool samples collected from hospitals in West Tehran and biochemical tests (TSI, SIM, MR&VP) were used to identify    E. coli species. Identification of genes pathovar diarrheal was carried out by use of multiplex PCR assay. Statistical data was performed with SPSS version 19, using (kruskal–Wallis one-way analysis of variance)  descriptive statistical analysis .
Results: A total of 55 of isolated clinical samples were identify as E. coli.  Gene stx1 was not identified in any of the samples. Among the identified genes, the highest frequency of responsible gene was stx2 with 12.72% and the lowest was for IPaH gene with 1.81%.
Conclusion: Frequency more Stx2 than other genes gene studied in this research can be seen as a major factor ‎in causing diarrhea caused by E. coli‏.‏‎ Multiplex PCR method can be in the shortest period of time ‎with high specificity and sensitivity to the presence of disease-causing genes discovered and be ‎prevented With appropriate and timely treatment of the creation of resistant strains and ‎transmission of these genes in the human population.‎


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