Outer Membrane Protein C (ompC) Gene as the Target for Diagnosis of Salmonella Species Isolated from Human and Animal Sources

Background: The use of selective and differential plating media is a simple method for the isolation of Salmonella spp. Recently, there has been a general move toward molecular methods of Salmonella detection and typing. Methods: A total of 1200 different specimens collected from human and animal sources were involved in his study. 600 stool specimens from patients suffering from diarrhea and 600 specimens from gall bladder (bile) of cattle from Al-Diwaniya slaughter house, Iraq were used. Salmonella spp. were isolated and identified using bacterial culturing on selective media and colonies were tested by API 20Eand then serotyping through polyvalent antisera and conformation by Polymerase Chain Reaction (PCR). PCR was used to detect ompC gene encoding biosynthesis of outer membrane protein C of Salmonella genus. Results: The results revealed that the rate of Salmonella isolates was 0.5% (3/600) from human and 1% (6/600) from animals. The PCR technique revealed that 9 isolates of Salmonella spp. harbored ompC gene. The results of this study revealed that the PCR technique had a high specificity in detection of Salmonella spp., in comparison to culture and biochemical test, Mini API 20 E and serological tests. The present study found no significant differences between human and animal isolates. Conclusion: Detection of ompC gene is a good method for detection of Salmonella species isolated from clinical specimens. It has a high specificity in comparison with other tests, with its advantages of greater speed and effectiveness than conventional detection methods.