title: Antimicrobial susceptibilities of Listeria monocytogenes strains isolated from food and food processing environment in Poland.
abstract: A total of 471 Listeria monocytogenes isolates from different types of food and food-related sources in Poland during 2004-2010 were examined. This number includes 200 isolates from fish, 144 from fresh and frozen vegetables, 43 ready-to-eat products (deli foods, cold cuts), 13 from dairy products, 16 from raw meats, 15 from confectionery products and 40 directly from processing plants. All isolates were subjected to serotyping and lineage assays using PCR, and antimicrobial susceptibility using E-test and a broth microdilution method. Of all isolates, 256 (54.4%), 120 (25.5%), 59 (12.5%), 36 (7.6%) were identified as serotypes 1/2a (or 3a), 1/2c (or 3c), 1/2b (or 3b or 7), and 4b (or 4d or 4e), respectively. A direct correlation between the most common serotypes and three L. monocytogenes lineages was also observed. All L. monocytogenes isolates belonged to lineages I (20.2%) and II (79.8%). All strains were sensitive to ampicillin, amoxicillin, gentamicin, erythromycin, trimethoprim, rifampicin, vancomycin, chloramphenicol and sulfamethoxazol. Two of the L. monocytogenes strains (0.42%) showed phenotypic resistance. One strain was resistant to tetracycline and minocycline due to the presence of tet(M). It did not carry gene int, which may indicate that the tet(M) gene in this strain was not integrated in the transposon Tn916-Tn1545 family. The resistance of the second strain to ciprofloxacin and norfloxacin was attributed to active efflux associated with overexpression of gene lde. Our data indicate the low prevalence of antimicrobial resistance among L. monocytogenes isolates from food and food-related sources in Poland.
authors.affiliation: Department of Applied Microbiology, Faculty of Biology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland. d.korsak@uw.edu.pl
authors.forename: Dorota
authors.initials: D
authors.lastname: Korsak
authors.forename: Anna
authors.initials: A
authors.lastname: Borek
authors.forename: Sylwia
authors.initials: S
authors.lastname: Daniluk
authors.forename: Anna
authors.initials: A
authors.lastname: Grabowska
authors.forename: Krystyna
authors.initials: K
authors.lastname: Pappelbaum
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003611:Dairy Products / Q000382:microbiology; D024881:Drug Resistance, Bacterial / Q000187:drug effects / Q000235:genetics; D005511:Food Handling; D005516:Food Microbiology; D008089:Listeria monocytogenes / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D008460:Meat / Q000382:microbiology; D011044:Poland; D016133:Polymerase Chain Reaction; D012703:Serotyping; D014675:Vegetables / Q000187:drug effects / Q000235:genetics / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents