Abstract

The aim of this study was to explore the taxonomic identification and evaluate the safety of a bacterium, Enterococcus lactis IDCC 2105, isolated from homemade cheese in Korea, using whole genome sequence (WGS) analysis. It sought to identify the species level of this Enterococcus spp., assess its antibiotic resistance, and evaluate its virulence potential. WGS analysis confirmed the bacterial strain IDCC 2105 as E. lactis and identified genes responsible for resistance to erythromycin and clindamycin, specifically msrC, and eatAv, which are chromosomally located, indicating a minimal risk for horizontal gene transfer. The absence of plasmids in E. lactis IDCC 2105 further diminishes the likelihood of resistance gene dissemination. Additionally, our investigation into seven virulence factors, including hemolysis, platelet aggregation, biofilm formation, hyaluronidase, gelatinase, ammonia production, and β-glucuronidase activity, revealed no detectable virulence traits. Although bioinformatic analysis suggested the presence of collagen adhesion genes acm and scm, these were not corroborated by phenotypic virulence assays. Based on these findings, E. lactis IDCC 2105 presents as a safe strain for potential applications, contributing valuable information on its taxonomy, antibiotic resistance profile, and lack of virulence factors, supporting its use in food products.

中文翻译：

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从自制乳制品中分离出的肠球菌菌株的基因组分类鉴定和安全性评估

摘要

本研究的目的是利用全基因组序列 (WGS) 分析，探索从韩国自制奶酪中分离出的细菌乳酸肠球菌IDCC 2105 的分类学鉴定并评估其安全性。它试图确定这种肠球菌属的物种水平，评估其抗生素耐药性，并评估其毒力潜力。WGS 分析证实细菌菌株 IDCC 2105 为乳酸大肠杆菌，并鉴定了负责红霉素和克林霉素抗性的基因，特别是msrC和eatAv，它们位于染色体上，表明水平基因转移的风险最小。乳酸乳球菌IDCC 2105中质粒的缺失进一步降低了抗性基因传播的可能性。此外，我们对七种毒力因子（包括溶血、血小板聚集、生物膜形成、透明质酸酶、明胶酶、氨产生和 β-葡萄糖醛酸酶活性）的研究未发现可检测到的毒力特征。尽管生物信息学分析表明存在胶原粘附基因acm和scm，但这些并未通过表型毒力测定得到证实。基于这些发现，乳酸乳球菌IDCC 2105 是一种具有潜在应用价值的安全菌株，提供了有关其分类学、抗生素耐药性特征和缺乏毒力因子的宝贵信息，支持其在食品中的使用。