Cerioli María F, Fernández Franco D, Moliva Melina V, Serral Federico, Fernandez Do Porto Darío, Reinoso Elina B
Departamento de Microbiología e Inmunología, Universidad Nacional de Río Cuarto, Ruta 36 Km 601. 5800 Río Cuarto, Córdoba, Argentina; INBIAS-CONICET, Universidad Nacional de Río Cuarto, Ruta 36 Km 601, 5800 Río Cuarto, Córdoba, Argentina.
Instituto de Patología Vegetal - Centro de Investigaciones Agropecuarias - Instituto Nacional de Tecnología Agropecuaria (IPAVE-CIAP-INTA), Camino 60 Cuadras Km 5, 5 (X5020ICA), Córdoba, Argentina; Unidad de Fitopatología y Modelización Agrícola - Consejo Nacional de Investigaciones Científicas y Técnicas (UFYMA-CONICET), Camino 60 Cuadras Km 5,5 (X5020ICA), Córdoba, Argentina.
Microb Pathog. 2025 Sep;206:107846. doi: 10.1016/j.micpath.2025.107846. Epub 2025 Jun 27.
Environmental bacteria, such as streptococci and enterococci, play an important role in bovine mastitis. This study aims to characterize the genome sequence of Enterococcus spp. isolated from a case of subclinical mastitis. Genomic DNA was isolated and sequenced using Illumina and Oxford Nanopore platforms. Final genome was assembled in a single circular chromosome and one plasmid comprising 2.556.630 bp (GC% 38.60) and 150.514 bp (GC 36 %), respectively. Phylogeny confirmed that strain SU-B46 is closely related to E. lactis reference genomes. The alignment confirmed the presence of E. lactis. Additionally, the genomic analysis identified twelve potential virulence genes related to adhesion, immune evasion and biofilm formation among others, but none were found in the plasmid. The strain exhibited resistance to aminoglycosides, macrolides and glycopeptides. This study presents the first report of an E. lactis strain isolated from a subclinical mastitis case in Argentina, broadening the geographical and host range of this pathogen. These findings suggest the possible involvement of E. lactis as an etiological agent of bovine mastitis. Further studies are needed to understand the significance of this agent, warranting additional investigation to ensure its optimal management, especially within the dairy industry.
环境细菌，如链球菌和肠球菌，在牛乳腺炎中起着重要作用。本研究旨在对从一例亚临床乳腺炎病例中分离出的肠球菌属的基因组序列进行表征。使用Illumina和牛津纳米孔平台分离并测序基因组DNA。最终基因组组装成一条单一的环状染色体和一个质粒，分别包含2556630 bp（GC含量38.60%）和150514 bp（GC含量36%）。系统发育分析证实菌株SU-B46与乳酸肠球菌参考基因组密切相关。比对证实了乳酸肠球菌的存在。此外，基因组分析鉴定出十二个与黏附、免疫逃避和生物膜形成等相关的潜在毒力基因，但在质粒中未发现。该菌株对氨基糖苷类、大环内酯类和糖肽类表现出抗性。本研究首次报道了从阿根廷一例亚临床乳腺炎病例中分离出的乳酸肠球菌菌株，拓宽了该病原体的地理和宿主范围。这些发现表明乳酸肠球菌可能作为牛乳腺炎的病原体。需要进一步研究以了解该病原体的重要性，有必要进行额外调查以确保对其进行最佳管理，尤其是在乳制品行业。
