• Journal of Microbiology and Biotechnology
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• 제32권12호
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• pp.1605-1614
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• 2022

The strains associated with foodborne Salmonella enterica Thompson outbreaks in Korea have not been identified. Therefore, we characterized S. Thompson strains isolated from chocolate cakes linked to foodborne outbreaks in Korea. A total of 56 strains were isolated from preserved cake products, products in the supply chain distribution, the manufacturer's apparatus, and egg white liquid products used for cream preparation. Subsequently, serological typing, pathogenic gene-targeted polymerase chain reaction (PCR), pulsed-field gel electrophoresis (PFGE), and whole-genome multi-locus sequence typing (wgMLST) were performed to characterize these isolates. The antigen formula of all isolates was 7:k:1,5, namely Salmonella enterica subsp. enterica Serovar Thompson. All 56 isolates harbored invA, his, hin, and stn, and were negative for sefA and spvC based on gene-targeted PCR analyses. Based on PFGE results, these isolates were classified into one group based on the same SP6X01.011 pattern with 100% similarity. We selected 19 strains based on the region and sample type, which were subjected to wgMLST. Although the examined strains showed 100% similarity, they were classified into seven clusters based on allelic differences. According to our findings, the cause of these outbreaks was chocolate cake manufactured with egg white liquid contaminated with the same Salmonella Thompson. Additionally, comparative analysis of wgMLST on domestic isolates of S. Thompson from the three outbreaks showed genetic similarities of over 99.6%. Based on the results, the PFGE and wgMLST combination can provide highly resolved phylogeny and reliable evidence during Salmonella outbreak investigations.

• 미생물학회지
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• 제54권2호
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• pp.155-157
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• 2018

Salmonella enterica subsp. enterica serovar Thompson strain MFDS1004024 는 2014 년 한국에서 발생한 식중독 사고의 게맛살에서 분리되었다. 본 연구에서는 4,742,942 bp 의 크기와 약 52%의 G + C 함량을 가진 MFDS1004024 균주의 완전한 유전체 염기서열을 분석하였다. 이 유전체에는 4,373 개의 코딩 서열, 22 개의 리보솜 RNA 유전자 및 84 개의 전사 RNA 유전자가 존재한다. 또한 유전체 분석 결과를 통해 살모넬라 감염과 베타락탐계 항생제 내성에 관련이 있는 유전자를 발견하였다.