title: High level of heterogeneity among Listeria monocytogenes isolates from clinical and food origin specimens in Greece.
abstract: In order to examine the genetic variation of clinical and food isolates of Listeria monocytogenes in Greece, a total of 61 L. monocytogenes non-duplicate isolates, recovered from clinical specimens (n=19) and food (n=42), were serotyped and genotyped using two different Random Amplification of Polymorphic DNA (RAPD) protocols and Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Serotype group 4b, 4d, 4e prevailed (39.4%), among both clinical and food isolates, followed by serotype group 1/2a, 3a (23.0%), which nevertheless was detected only among food isolates. The most discriminatory typing protocol was MLVA, which grouped four isolates into two pairs, while the remaining isolates produced unique fingerprints. Similar results were obtained when taking into account the combination of the two RAPD protocols (Simpson index 0.999); six isolates were grouped into three pairs, two of which were the pairs that were identified also by MLVA. Single use of each RAPD protocol resulted in inferior discrimination (Simpson index 0.978 and 0.997, respectively). In conclusion, the two molecular procedures, MLVA, and the combined RAPD protocols, produced similar results, showing that L. monocytogenes isolates from clinical and food specimens were highly heterogenous and that clustering was very uncommon.
authors.affiliation: Department of Food Technology, Technological Educational Institute of Athens, Aigaleo, Greece.
authors.forename: Dimitra P
authors.initials: DP
authors.lastname: Houhoula
authors.forename: Dimitra
authors.initials: D
authors.lastname: Peirasmaki
authors.forename: Spyros J
authors.initials: SJ
authors.lastname: Konteles
authors.forename: Dimosthenis
authors.initials: D
authors.lastname: Kizis
authors.forename: Stamatis
authors.initials: S
authors.lastname: Koussissis
authors.forename: Michael
authors.initials: M
authors.lastname: Bratacos
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Poggas
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Charvalos
authors.forename: Athanassios
authors.initials: A
authors.lastname: Tsakris
authors.forename: Joseph
authors.initials: J
authors.lastname: Papaparaskevas
mesh_terms: D000818:Animals; D016470:Bacteremia / Q000097:blood / Q000134:cerebrospinal fluid / Q000382:microbiology; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D005516:Food Microbiology; D005517:Foodborne Diseases / Q000097:blood / Q000134:cerebrospinal fluid / Q000382:microbiology*; D014644:Genetic Variation; D006115:Greece; D006786:Hospitals, Urban; D006801:Humans; D008089:Listeria monocytogenes / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D008088:Listeriosis / Q000097:blood / Q000134:cerebrospinal fluid / Q000382:microbiology*; D008460:Meat / Q000382:microbiology; D058889:Molecular Typing; D060885:Multiplex Polymerase Chain Reaction; D019105:Random Amplified Polymorphic DNA Technique; D012703:Serotyping; D020080:Tandem Repeat Sequences
chemical_list: D004269:DNA, Bacterial