To troubleshoot this issue, we accounted for this heterogeneity during the establishment of the RMS library (MSL). We hypothesized that MS identification effectiveness could be enhanced by increasing both the number of reference meta spectra (RMS) of a given strain included in the Stattic cell line reference library and the number of deposits used to generate each RMS. The primary objective of this study was to test the effectiveness of distinct reference spectra library architectures for the MALDI-TOF MS-based identification of filamentous fungi. More

precisely, we assessed the influence on identification effectiveness of the following: i) the number of technical replicates, i.e., the number of analyzed deposits (spots) from one culture used to generate an RMS; ii) the number of biological Vactosertib ic50 replicates, i.e., the number of RMS derived from distinct subcultures for each strain; and iii) the number of distinct strains of one species used to

construct the library. Figure 1 Comparison of mass spectra obtained from four subcultures of a strain of Aspergillus flavus. The Aspergillus flavus 1027804 strain was find more subcultured on four different agar plates. Spectra A, B, C, and D display the

mTOR inhibitor first spectrum acquired from the subcultures 1, 2, 3 and 4, respectively. Spectra A to D display many common peaks; however, a few varying peaks are also clearly visible and characteristic of one of the subcultures. Results Phenotypic and genotypic identification of clinical isolates The results of the classical and DNA sequence-based identification of 200 clinical isolates (Table 1) were applied to classify the isolates into two groups: isolates included and isolates excluded from the MSL. The MS results of both groups are summarized in Table 2. The isolates belonged to 28 different genera and 38 different species. Moreover, 174 isolates corresponded to 18 species, which were represented among those used to construct the eight libraries, whereas the 26 remaining isolates belonged to 20 species that were not represented in the libraries. Table 1 Identification of the 200 clinical isolates included in the study Species Number of Isolates Corresponding RMS in the MSLs Acremonium sp.