Evaluation of a novel sample preparation method for identifying Aspergillus fumigatus using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry: Combining Yatalase and silica beads treatment.

Aspergillus spp. belong to filamentous fungi and sometimes cause invasive aspergillosis which has high mortality. Filamentous fungi are generally identified morphologically. However, morphologic identification is time consuming and requires advanced skills. It is difficult to train technicians and ensure a high level of quality. Therefore, an identification technique that is both accurate and relatively easy to learn is needed. In the present study, we focused on the effects of Yatalase and silica beads, which enable the efficient extraction of proteins via cell wall disruption of Aspergillus spp., and aimed to establish a novel sample preparation method using Yatalase and silica beads to enhance the efficiency of Aspergillus spp. identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The sample preparation method using the combination of Yatalase and silica beads showed higher accuracy for the identification of Aspergillus spp. compared with Yatalase or silica beads alone. The Yatalase/silica beads method also resulted in significantly higher identification scores compared with the conventional method for the identification of Aspergillus fumigatus (n = 33). These findings indicate that our novel Yatalase/silica beads method provides more reliable identification of A. fumigatus than does the conventional method.