Longitudinal study on Listeria monocytogenes in Sardinian fermented meat products processing plants: contamination routes, pathogenic profile and evaluation of gene expression in persistent and non-persistent isolates

摘要: Detection and enumeration of L. monocytogenes have been carried out in 385 samples raw materials, fermented sausages environments different processing plants located Sardinia (Italy). A subset ninety - seven strains isolated during a period from 2004 to 2011 were characterized by multiplex PCR-based serogrouping, PCRs for the presence virulence genes, PFGE, quantitative assessment vitro biofilm formation. In addition, Relative Absolute Quantification genes expression pocR , mdr eutG cbiD probably involved persistence pathogen environment evaluated, persistent non-persistent isolates Real-Time PCR. The 22% positive . 31.51% 15% tested, food environment, respectively, Listeria monocytogenes. Isolates serotyped as 1/2a, 1/2c, 1/2c 4b, presented all considered genes. PFGE revealed high heterogeneity pulsotypes within plants. results did not showed among selection included this study. 44% tested able attach abiotic surfaces forming biofilm. qRTi-PCR that selected persistence.