بررسی حضور ژن prf A در لیستریا مونوسیتوژنز جداسازی شده از مواد غذایی

Background: listeria is a gram-positive bacterium and a facultative food- borne intracellular pathogen. prf a gene regulates the expression of other genes and is important in virulence. objective: the aim of this study was to identify prf a gene in listeria monocytogenes isolated from food samples.methods: this cross - sectional study was conducted in 212 different food samples collected from different cities in 2012. listeria monocytogenes was isolated using the cold enrichment method. the prf a gene was identified using polymerase chain reaction (pcr). data were analyzed using chi- square test. findings: of 212 samples, 41 (%19.33) were positive for listeria spp. of 41, 22 (%53.6) were listeria monocytogenes, 15 (%36.5) were l. innocua, 3 (%7.3) were l. welshimri and 1 (%2.4) was l. seeligeri. the prf a gene was found in 28.5% of l. monocytogenes isolated from vegetable samples and in 100% l. monocytogenes isolated from other samples.conclusion: confirmation of the presence of l. monocytogenes in food and the prf a gene may be helpful to prevent diseases caused by listeria.