Molecular Study about some Genes among Salmonella Typhi Isolates un Hilla / Iraq

In this study, (100) blood sample were collected from patient suspected with typhoid fever how were visits the Alhashimiya, Hilla Teaching Hospital and Morjan Teaching Hospital in Babylon province (Iraq) during the period November (2018) to February (2019). Identification was done by cultural and biochemical tests, and finally identification by Vitek2. Results showed that positive were (16) isolates of Salmonella enteric serovar typhi by Vitek2 (16%) from the(100) blood. Molecular study was accomplished first by the isolation of DNA from Salmonella typhi isolates, they used method had succeeded in extraction of genomic DNA from all isolates. Second by using PCR technique to detection four gene by using a specific PCR primer were done by comparison with allelic ladder which gave a (578bp) it was found that (flicA) gene present in (15) isolates (93.75%) of the positive sample. viaB gene was also detected in S. typhi sample and found that in (15) isolates (93.75%) of the positive sample which gave molecular length (438bp) band. Molecular detection of sipA gene in S. typhi present of this gene in all (16) isolated (100%) positive, which gave molecular length (1126bp). Molecular detection of sdiA gene was done for (16) isolated of S. typhi, and the results showed that (15) isolates (93.75%) the positive results for sdiA virulence were detected by the presence of (274bp) band compared with allelic ladder. This study was conducted to identify the presence of Salmonella enterica serovar typhi within five isolated bacterial samples. One genetic locus covering a particular coding portion within the sdiA gene, which is responsible on the encoding of cell-division regulatory protein, was selected for amplification