AUTHOR=Wei Linwei , Shao Jin , Song Yinggai , Wan Zhe , Yao Limin , Wang Hong , Yu Jin 

TITLE=Performance of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Scedosporium, Acremonium-Like, Scopulariopsis, and Microascus Species

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.841286

DOI=10.3389/fmicb.2022.841286

ISSN=1664-302X

ABSTRACT=<p>Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has emerged as a powerful microorganism identification tool. Research on MALDI-TOF MS identification of rare filamentous fungi is still lacking. This study aimed to evaluate the performance of MALDI-TOF MS in the identification of <italic>Scedosporium</italic>, <italic>Acremonium</italic>-like, <italic>Scopulariopsis</italic>, and <italic>Microascus</italic> species. Sabouraud broth cultivation and formic acid/acetonitrile protein extraction were used for MALDI-TOF MS identification by a Bruker Biotyper system. An in-house database containing 29 isolates of <italic>Scedosporium</italic>, <italic>Acremonium</italic>-like, <italic>Scopulariopsis</italic>, and <italic>Microascus</italic> spp. was constructed. A total of 52 clinical isolates were identified using the Bruker Filamentous Fungi Library v1.0 (FFL v1.0) alone, and Filamentous Fungi Library v1.0 plus the in-house library, respectively. The mass spectrum profile (MSP) dendrograms of the 28 <italic>Scedosporium</italic> isolates, 26 <italic>Acremonium</italic>-like isolates, and 27 <italic>Scopulariopsis</italic> and <italic>Microascus</italic> isolates were constructed by MALDI Biotyper OC 4.0 software, respectively. The correct species identification rate significantly improved when using the combined databases compared with that when using FFL v1.0 alone (<italic>Scedosporium</italic> spp., 75% versus 0%; <italic>Acremonium</italic>-like spp., 100% versus 0%; <italic>Scopulariopsis</italic> and <italic>Microascus</italic> spp., 100% versus 62.5%). The MSP dendrograms differentiated <italic>Acremonium</italic>-like species, <italic>Scopulariopsis</italic> and <italic>Microascus</italic> species clearly, but cannot distinguish species in the <italic>Scedosporium apiospermum</italic> complex. In conclusion, with an expanded database, MALDI-TOF MS is an effective tool for the identification of <italic>Scedosporium</italic>, <italic>Acremonium</italic>-like, <italic>Scopulariopsis</italic>, and <italic>Microascus</italic> species.</p>