Evaluation of selected Listeria monocytogenes genotyping methods
Madajczak, G.
Medycyna Doswiadczalna i Mikrobiologia 58(4): 329-337
2006
ISSN/ISBN: 0025-8601 PMID: 17642310 Document Number: 599428
Listeria monocytogenes infections are found in Poland and all world as sporadic episodes and large outbreaks of human illness as well, where bacteria-contaminated food is the source of infection. Genotyping of strains isolated from outbreak is one of many other stages of epidemiologic investigation. In case of L. monocytogenes pulse-field gel electrophoresis (PFGE) - "golden standard" of genotyping and also ERIC-PCR and rep-PCR could be used. The goal of this study was to evaluate the usefulness of methods: PFGE, ERIC-PCR and rep-PCR to Listeria monocytogenes strains genotyping. Moreover estimation of L. monocytogenes strains isolated in Poland during 2003 - 2006 years genetic diversity was performed. In performed studies, 44 strains of L. monocytogenes from PZH strains collection from 2003 - 2006 period were used. Standard strains of L. monocytogenes, L. ivanovii, L. welschimeri and L. innocua were used also. All those strains were genotyped using following methods: PFGE with ApaI and AscI restrictases and random amplification of polymorphic DNA fragments (ERIC-PCR, rep-PCR). Obtained results were analyzed using Tenover method and specialistic software - Gene Profiler (Scan Analytics, USA). In every analysis, clonal groups were obtained - using computer analysis as well as Tenover method. For PFGE with ApaI and AscI six clonal groups were obtained in each analysis. For ERIC-PCR and rep-PCR four clonal groups were obtained (every group was different except one, where four the same strains were included). Taking into account such factors, as efficiency of strains differentiation, work consumption and costs of procedure performing, for quick application, especially in local laboratories, the best genotyping technique is rep-PCR and ERIC-PCR a little less. On account of appreciable costs of PFGE analysis, this method should be used as reference technique.