Multi-centric evaluation of the online MSI platform for the identification of cryptic and rare species of Aspergillus by MALDI-TOF
Multi-centric evaluation of the online MSI platform for the identification of cryptic and rare species of Aspergillus by MALDI-TOF
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DOI：
10.1093/mmy/myz004
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发表时间：
2019-11-01
期刊：
影响因子：
2.9
通讯作者：
Fekkar, Arnaud
中科院分区：
文献类型：
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作者：
Imbert, Sebastien;Normand, Anne Cecile;Fekkar, Arnaud
曲霉属物种的分类学最近随着神秘物种和部分概念的引入而发生了革命性的变化。然而，在常规实验室进行物种一级的鉴定仍然是一个挑战。本研究的目的是前瞻性地评估使用质谱鉴定（MSI）平台（一个独立且可免费访问的在线质谱数据库）在各个实验室中对曲霉菌隐种的鉴定准确性。在12个月的时间里，当一组选定的MSI用户识别出神秘物种时，他们被联系并要求将分离株送到我们的实验室进行基于序列的鉴定。然后比较序列和MSI鉴定结果。在研究期间，5108曲霉菌株鉴定MSI包括1477（28.9%）的神秘物种。随机选择了245株分离株（对应于56个隐种和13个切片）进行DNA测序确认。两种方法的一致性在组水平上为99.6%，在种水平上为66.1%。然而，几乎所有的差异（72/83，86.7%）是属于同一组的密切相关的隐种之间的错误鉴定。还确定了51株非隐性种，从而产生100%和92.2%的协议，在部分和种的水平，分别。虽然MSI真菌数据库是一个可靠的工具，以确定曲霉属在部分水平，该数据库仍然需要调整，以正确地确定罕见或神秘的物种在物种水平。然而，该应用程序正确区分了同一节中的神秘种和狭义种，从而提醒注意可能的特定分离株特征。
The taxonomy of Aspergillus species has recently been revolutionized with the introduction of cryptic species and section concepts. However, their species-level identification in routine laboratories remains a challenge. The aim of this study was to prospectively assess the identification accuracy of cryptic species of Aspergillus in various laboratories using the mass spectrometry identification (MSI) platform, an independent and freely accessible online mass spectrometry database. Over a 12-month period, when a select set of MSI users identified cryptic species, they were contacted and requested to send the isolates to our laboratory for sequence-based identification. Sequence and MSI identification results were then compared. During the study period, 5108 Aspergillus isolates were identified using MSI including 1477 (28.9%) cryptic species. A total of 245 isolates that corresponded to 56 cryptic species and 13 sections were randomly selected for DNA sequencing confirmation. Agreement between the two methods was 99.6% at the section level and 66.1% at the species level. However, almost all discrepancies (72/83, 86.7%) were misidentifications between closely related cryptic species belonging to the same section. Fifty-one isolates from noncryptic species were also identified, thus yielding 100% and 92.2% agreement at the section and species level, respectively. Although the MSI fungus database is a reliable tool to identify Aspergillus at the section level, the database still requires adjustment to correctly identify rare or cryptic species at the species level. Nevertheless, the application properly differentiated between cryptic and sensu stricto species in the same section, thus alerting on possible specific isolate characteristics.