Staphylococcus aureus represent a serious threat to public health due to food safety, antibiotic resistance, and the potential zoonotic transmission of strains between dairy cattle and humans. Biofilm formation by S. aureus results in chronicity of the infections which confers protection against the immune response and antibiotics. Likewise, biofilm allows the exchange of mobile genetic material among different strains through microbial interactions inside the matrix. In Colombia, where S. aureus continues to be one of the main pathogens isolated from bovine intramammary infections and where milking by hand is highly frequent, there are knowledge gaps on the zoonotic potential of the strains. Therefore, the aim of this work was to characterize genotypically and phenotypically the S. aureus Sa1FB strain with strong biofilm production and to perform genomic and phenotypic comparisons with other relevant S. aureus strains (native and references strains). These results show a highly productive strain of biofilm and a low ability of cell invasion compared to the other two native strains. In addition, high genomic similarity between S. aureus Sa1FB and the reference strains was observed, despite of the differences reported at the clinical level. However, Sa1FB exhibited special features in terms of mobile genetic elements, highlighting its ability to accept foreign genetic material. Indeed, this could increase mutation, pathogenesis, and adaptability to new hosts, representing a risk for people in contact with the milk obtained from animals infected with these strains. These results present the relevance of surveillance for early detection of emergent clones with zoonotic potential, which reduces the risk of occupational exposure and their spread in the community.

金黄色葡萄球菌由于食品安全、抗生素耐药性以及奶牛和人类之间潜在的人畜共患菌株传播，这些细菌对公众健康构成了严重威胁。生物膜的形成金黄色葡萄球菌导致慢性感染，从而提供针对免疫反应和抗生素的保护。同样，生物膜允许通过基质内的微生物相互作用在不同菌株之间交换可移动遗传物质。在哥伦比亚，哪里金黄色葡萄球菌仍然是从牛乳房内感染中分离出的主要病原体之一，并且在手工挤奶非常频繁的情况下，对该菌株的人畜共患潜力存在知识空白。因此，这项工作的目的是从基因型和表型上表征金黄色葡萄球菌Sa1FB 菌株具有强大的生物膜生成能力，可与其他相关菌株进行基因组和表型比较金黄色葡萄球菌菌株（天然菌株和参考菌株）。这些结果表明，与其他两种天然菌株相比，该菌株的生物膜生产力高，细胞侵袭能力低。此外，基因组之间的高度相似性金黄色葡萄球菌尽管临床水平报告存在差异，但仍观察到 Sa1FB 和参考菌株。然而，Sa1FB在可移动遗传元件方面表现出特殊的特征，突出了其接受外来遗传物质的能力。事实上，这可能会增加突变、发病机制和对新宿主的适应性，从而给接触感染这些菌株的动物的牛奶的人带来风险。 这些结果表明了监测对于早期发现具有人畜共患潜力的新兴克隆的相关性，从而降低了职业暴露及其在社区传播的风险。