Abstract：
Bovine mastitis is the most common disease affecting dairy cattle worldwide and it generates substantial losses for cattle breeders. One of the most common pathogens identified in infected milk samples is Staphylococcus aureus. Currently, there is no fast test for recognizing bacteria species on the market. The aim of this study was to bioinformatically and laboratory detect and characterize the fibronectin binding protein A (FnBPA) of S. aureus (SA) in milk samples obtained from cows diagnosed with mastitis. More than 90,000,000 amino acid sequences were subjected to bioinformatic detection in the search for a potential biomarker for bovine SA. The analysis of FnBPA included the detection of signal peptides and nonclassical proteins, antigenicity, and the prediction of epitopes. To confirm the presence of the fnbA gene in four SA isolates, amplification with specific primers was performed. FnBPA was detected by immunoblotting. The immunoreactivity and selectivity were performed with monoclonal anti-FnBPA antibodies and SA-negative serum. The bioinformatic analysis showed that FnBPA is a surface, conservative, immunoreactive, and species-specific protein with antigenic potential. Its presence was confirmed in all of the SA isolates we studied. Immunoblotting proved its immunoreactivity and specificity. Thus, it can be considered a potential biomarker in mastitis immunodiagnostics.
摘要：
牛乳腺炎是世界范围内影响奶牛的最常见疾病,并且它对牛饲养者造成重大损失。在受感染的牛奶样品中鉴定出的最常见的病原体之一是金黄色葡萄球菌。目前,没有快速测试来识别市场上的细菌种类。这项研究的目的是通过生物信息学和实验室检测和表征从诊断为乳腺炎的奶牛获得的牛奶样品中金黄色葡萄球菌（SA）的纤连蛋白结合蛋白A（FnBPA）。对超过90,000,000个氨基酸序列进行生物信息学检测,以寻找牛SA的潜在生物标志物。FnBPA的分析包括信号肽和非经典蛋白的检测，抗原性,和表位的预测。为了证实fnbA基因在四个SA分离株中的存在，用特异性引物进行扩增。通过免疫印迹检测FnBPA。用单克隆抗FnBPA抗体和SA阴性血清进行免疫反应性和选择性。生物信息学分析表明，FnBPA是一个表面，保守,免疫反应性，和具有抗原潜力的物种特异性蛋白质。在我们研究的所有SA分离物中都证实了它的存在。免疫印迹证明了其免疫反应性和特异性。因此，它可以被认为是乳腺炎免疫诊断的潜在生物标志物。
