Molecular Characterization of <i>Listeria monocytogenes</i> Based on the PFGE and RAPD in Korea

Abstract

This study was performed to characterize 35 L. monocytogenes isolates from animals, foods, environmental samples collected between 1997 and 2007 with no apparent epidemiological relations, and five reference isolates using serotypic, genotypic and molecular typing methods to understand the pattern of strain distribution in Korea. For this study, we used serotyping and detected 6 different virulence-associated genes (inlA, inlB, plcA, plcB, hlyA, and actA) and 16s rRNA using multiplex-PCR. We also compared RAPD and PFGE to determine genetic characterization of L. monocytogenes strains to define the genetic diversity. Serotype patterns of the 30 L. monocytogenes strains was as follows; 9 isolates (30.0 %) belonged to serotype, 7 isolates (23.3%) belonged to serotype 4b, 4 isolates (13.3%) belonged to serotype 1/2b, 3 isolates (10.0%) belonged to serotype 1/2c, 2 (6.7%) isolates belonged to 4c, 2 (6.7%) isolates belonged to NT (Non Type), one isolate (3.2%) belonged to 3a and 3b, and 4a, respectively. Although, a limited number of isolates were analyzed in this study, molecular typing with RAPD and PFGE indicated that PFGE is more discriminatory for the subtyping L. monocytogenes than RAPD. Some L. monocytogenes isolates by RAPD and PFGE types are associated with specific sources. And, combining data obtained by these methods will increases the likelihood of strain discrimination.

Increasing Incidence of Listeriosis and Infection-associated Clinical Outcomes

“…Listeriosis caused by Listeria monocytogenes is a bacterial infection with a high case-fatality rate (CFR) of approximately 20% to 30%; listeriosis occurs mainly in the elderly, neonates, immunocompromised patients, and pregnant women via central nervous system (CNS) infection and bloodstream infection (BSI) [ 1 2 3 4 ]. This gram-positive intracellular bacterium is widespread in the natural environment [ 5 ], and infections mostly arise following the consumption of contaminated food, such as unheated ready-to-eat meals and dairy products [ 6 7 8 ], because of the ability of L. monocytogenes to survive under salty or acidic conditions and grow at refrigeration temperatures [ 9 ].…”

Occurrence of Listeria monocytogenes on the seafood contact surfaces of Tuticorin Coast of India

“…Gawade et al (2010) also reported that L. monocytogenes can be confirmed by PCR using hlyA gene as a marker to differentiate L. monocytogenes from the other Listeria spp. In the present study, the PCR amplification of hlyA gene for the identification of L. monocytogenes used a set of primers as described by Park et al (2012) which yielded a product of 174 bp. The Type culture (MTCC 1143) and the isolates of L. monocytogenes from seafood contact surfaces swab yielded a similar product size of 174 bp on PCR amplification targeting hlyA gene (Fig.…”

“…Ltd., Mumbai, India) according to the manufacturer's protocol and stored at -20°C until further use. Oligonucleotide primers for the PCR assay were selected based on the earlier published nucleotide sequence of hlyA gene (Ndahi et al 2013;Park et al 2012). Forward primer is 5 0 -GCATCTGCATTCAATAAAGA-3 0 and reverse primer is 5 0 -TGTCACTGCATCTCCGTGGT-3 0 with a product size of 174 bp.…”

“…PCR is one of the molecular methods that are reliable, rapid and less time consuming (Almeida and Almeida 2000). PCR has been used for the detection of L. monocytogenes from seafood and their contact surfaces (Park et al 2012). One of the best ways to detect the pathogen is through targeting a virulence factor, listeriolysin O (LLO), produced by L. monocytogenes.…”

Comparison of selected disinfectants efficiency against Listeria monocytogenes biofilm formed on various surfaces

“…The isolates' genetic similarity evaluation was performed with the RAPD technique (Random Amplification of Polymorphic DNA) (Park et al 2012). The reaction was performed using the OPA-11 primer with the 5'-CAATCGCCGT-3′ sequence (Ozbey et al 2006).…”