Isolation of Listeria monocytogenes from meat products and study on prfA gene in bacteria isolated and compaire them with clinical samples and standard samples

Backgrounds and Listeria is a gram positive bacterium، facultive intracellular pathogene. prf A gene has an important role in virulence. The purpose of this study was to determine of the presence of Listeria monocytogenes in various meat products and presence of prf A gene in bacteria isolated from food samples and compare them with clinical samples and standard samples. During 6 months of 60 samples of beef، chicken، ham، cocktail، sausage، from a butchery’s Khoramabad and shops in Khoramabad and Tehran were collected. L. monocytogenes was isolated according to cold enrichment method and prf A gene were analyzed by PCR (Polymerase chain reaction) method. Statistical analysis was performed with the software SPSS (Statistical package for social science). From 60 samples of meat and meat products، 8 (%13. 3) were positive for Listeria spp. Among in these samples، 4 cases of L. monocytogenes (% 6. 6)، 3 cases (%5)، L. innocua and 1 case (%1. 6) L. welshimri، were isolated which L. innocua was isolated from meat and poultry samples and L. monocytogens from meat، chicken، ham and L. welshimeri from meat were isolated. Prf A gene was detected in isolated L. monocytogenes and donated bacteria from dairy products، clinical and standard samples، 2 cases of donated samples of vegetable contained prf A genes. The prf A gene (activator of transcription and regulators the expression of other virulence genes)، in the studied samples were observed. This gene plays a role in pathogenesis. Because these bacteria are transmitted through food and is a serious threat to public health. Thus identification of bacteria especially its genes could be possible to find some ways to prevent the bacteria and avoid disease from it.