Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS), a culture based alternative for microbial diversity studies, is an attractive tool to dereplicate large numbers of isolates to a smaller set of representatives for downstream characterization. In the present study, MALDI-TOF MS, combined with a database of reference spectra compiled in previous studies, was applied to identify 88 non-starter lactic acid bacteria (NSLAB) isolated from 18 samples of four different artisanal cheeses produced in the Island of Naxos, Greece, from raw sheep and goat milk without the addition of starters. Eighty-four isolates (95.5%) could be identified directly via MALDI-TOF MS. Lactobacillus brevis and Lactobacillus plantarum were the dominant species, followed by Lactococcus lactis, Leuconostoc mesenteroides Lactobacillus paracasei, Lactobacillus rhamnosus, Pediococcus pentosaceus and Enterococcus faecium. The remaining four isolates represented species present in the database; however, within-species diversity was insufficiently covered. Additionally, pheS sequencing was applied to confirm identification.

中文翻译：

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MALDI-TOF MS分析来自希腊纳克索斯岛手工奶酪的非发酵乳酸菌。

基质辅助激光解吸/电离飞行时间（MALDI-TOF）质谱（MS）是一种基于培养物的微生物多样性研究替代品，是将大量分离物复制为下游的较小代表的一种有吸引力的工具表征。在本研究中，MALDI-TOF MS与先前研究中收集的参考光谱数据库相结合，用于鉴定88种非发酵剂乳酸菌（NSLAB），这些细菌是从新西兰岛生产的四种不同手工奶酪的18个样品中分离出来的。希腊纳克索斯（Naxos）是从生绵羊和山羊奶中提取的，无需添加发酵剂。可以通过MALDI-TOF MS直接鉴定出八十四种分离株（95.5％）。短乳杆菌和植物乳杆菌是优势种，其次是乳酸乳球菌，mesenteroides mesenteroides副干酪乳杆菌，鼠李糖乳杆菌，戊糖小球菌和粪肠球菌。其余的四个分离株代表数据库中存在的物种。但是，物种内部的多样性没有得到足够的覆盖。另外，使用pheS测序来确认身份。