The current work investigated the discriminatory potential of MALDI-TOF MS fingerprinting towards most-relevant major (Streptococcus agalactiae, S. dysgalactiae, S. uberis) and minor (S. canis, S. parauberis, S. salivarius, S. equinus and S. gallolyticus) streptococci involved in bovine mastitis (BM), in comparison to 16S rRNA gene sequencing (GS)-based identification. The MALDI-TOF MS-generated spectral fingerprints were recruited for eliciting a detailed proteomic map that demonstrated clear variability for inter- and intra-species-specific biomarkers. Besides, a phyloproteomic dendrogram was evolved and comparatively analyzed against the phylogenetic one obtained from 16S rRNA GS in order to assess the differentiation of streptococci of bovine origin based on variability of protein fingerprints versus the variation of 16S rRNA gene homology. Results showed that the discrimination of BM-implicated streptococci can be obtained by both approaches; however MALDI-TOF MS was superior, achieving more variability at both intra- and sub-species levels. MALDI-TOF MS spectral analytics revealed that Streptococcus spp. exhibited three genus-specific biomarkers (peaks with m/z values at 2112, 4452 and 5955) and all streptococci exhibited spectral variability at both species and subspecies levels. Remarkably, MALDI-TOF MS fingerprinting was found to be at least as robust as 16S rRNA GS-based identification, allowing much cheaper and faster analysis, and additionally exhibiting high reliability for characterization of BM-implicated streptococci, thus proving to be a powerful tool that can be used independently within dairy diagnostics.

目前的工作调查MALDI-TOF MS指纹对潜在的歧视最相关专业（无乳链球菌，停乳链球菌，乳房链球菌）和未成年人（S.犬，S. parauberis，唾液链球菌，链球菌马蹄和小号鸡解毒与基于16S rRNA基因测序（GS）的鉴定相比，链球菌参与了牛乳腺炎（BM）。募集了MALDI-TOF MS产生的光谱指纹，以引发详细的蛋白质组图，该图显示了种间和种内特异性生物标记物的明显变异性。此外，为了从蛋白质指纹图谱的可变性与16S rRNA基因同源性的差异出发，评估牛源链球菌的分化，对从16S rRNA GS获得的系统进化树进行进化和比较分析。结果表明，两种方法均可鉴别出与BM相关的链球菌。然而，MALDI-TOF MS却很出色，在种内和亚种水平上均实现了更大的可变性。MALDI-TOF MS质谱分析表明链球菌属。展示了三个属特异性生物标志物（峰值在2112、4452和5955处的m / z值），所有链球菌在物种和亚种水平上均表现出光谱变异性。值得注意的是，发现MALDI-TOF MS指纹图谱至少与基于16S rRNA GS的指纹图谱一样强大，可进行更便宜，更快速的分析，并且对于表征BM链球菌具有很高的可靠性，因此被证明是有力的工具可以在乳制品诊断程序中独立使用。