Brucellosis' surveillance and control programs require robust laboratory techniques that can reliably identify and biotype Brucella strains and discriminate between vaccine and field infection. In the recent years, Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) has revolutionized the routine identification of several microorganisms in clinical microbiology laboratories. Nevertheless, its application on Brucella spp. identification is limited since there are no reference spectra in the commercial databases, due to the microorganism's potential bioterrorist use. In this study, a custom MALDI-TOF MS reference library was constructed and its performance on identification at species level was evaluated using 75 Brucella spp. isolates. Furthermore, distinct peak biomarkers were detected for biovar assignment and discrimination from vaccine strain Rev.1. Analysis of mass peak profiles allowed Brucella accurate identification at genus and species level (100%) with no misidentifications. Despite the high intrageneric similarity, MALDI-TOF MS database succeeded in classifying at biovar level, 47 out of 62 B. melitensis bv. 3 isolates (75.81%), whereas all B. melitensis strains, except for one, were correctly discriminated from vaccine strain Rev.1. MALDI-TOF MS appeared to be a rapid, cost-effective and reliable method for the routine identification of brucellae which reduces time consumption in pathogen identification and could replace in the near future the current conventional and molecular techniques. Its ability to differentiate vaccine from field infection could facilitate brucellosis' monitoring systems contributing in the effective control of the disease.

中文翻译：

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布鲁氏菌属的鉴定。通过MALDI-TOF质谱从疫苗菌株Rev.1中分离和鉴别。

布鲁氏菌病的监视和控制程序需要可靠的实验室技术，这些技术可以可靠地鉴定布鲁氏菌菌株并对其进行生物分型，并区分疫苗和现场感染。近年来，基质辅助激光解吸电离飞行时间质谱仪（MALDI-TOF MS）彻底改变了临床微生物学实验室对几种微生物的常规鉴定方法。尽管如此，它在布鲁氏菌属上的应用。由于微生物的潜在生物恐怖用途，商业数据库中没有参考光谱，因此鉴定受到限制。在这项研究中，构建了一个定制的MALDI-TOF MS参考库，并使用75 Brucella spp评估了其在物种水平上的鉴定性能。隔离株。此外，从疫苗菌株Rev.1中检测到了不同的峰生物标志物，以用于生物变量分配和区分。质谱峰分布图的分析使布鲁氏菌在属和种水平（100％）准确鉴定，没有错误鉴定。尽管内部相似度很高，但MALDI-TOF MS数据库还是成功地在biovar级别上进行了分类，在62个B. melitensis bv中有47个。3个分离株（占75.81％），而所有B. melitensis菌株（除1个外）均与疫苗菌株Rev.1正确区分。MALDI-TOF MS似乎是用于布鲁氏菌常规鉴定的一种快速，经济高效且可靠的方法，可减少病原体鉴定中的时间消耗，并可以在不久的将来取代当前的常规和分子技术。它区分疫苗和野外感染的能力可能促进布鲁氏菌病。