Identification of Volatile Sulfur Compounds Produced by Schizophyllum commune.

Takahito Toyotome,Maki Yahiro,Katsuhiko Kamei,Masahiro Takaya,Masahiko Takino

doi:10.3390/jof7060465

Abstract

Schizophyllum commune is a causative agent of allergic bronchopulmonary mycosis, allergic fungal rhinosinusitis, and basidiomycosis. Diagnosis of these diseases remains difficult because no commercially available tool exists to identify the pathogen. Unique volatile organic compounds produced by a pathogen might be useful for non-invasive diagnosis. Here, we explored microbial volatile organic compounds produced by S. commune. Volatile sulfur compounds, dimethyl disulfide (48 of 49 strains) and methyl ethyl disulfide (49 of 49 strains), diethyl disulfide (34 of 49 strains), dimethyl trisulfide (40 of 49 strains), and dimethyl tetrasulfide (32 of 49 strains) were detected from headspace air in S. commune cultured vials. Every S. commune strain produced at least one volatile sulfur compound analyzed in this study. Those volatile sulfur compounds were not detected from the cultures of Aspergillus spp. (A. fumigatus, A. flavus, A. niger, and A. terreus), which are other major causative agents of allergic bronchopulmonary mycosis. The last, we examined H2S detection using lead acetate paper. Headspace air from S. commune rapidly turned the lead acetate paper black. These results suggest that those volatile sulfur compounds are potent targets for the diagnosis of S. commune and infectious diseases.

Highlights

A basidiomycetous fungus Schizophyllum commune is a common mushroom that is found frequently in the environment, especially on withered trees
By gas chromatography (GC)/MS analysis using 49 S. commune strains cultured in securely sealed vials for 29 days, we detected five volatile sulfur compounds (VSCs) as major volatile organic compounds (VOCs) (Figure 1 and Table S2)
The ion count of Diethyl disulfide (DEDS) showed a weaker correlation with DMDS, dimethyl trisulfide (DMTriS), or DMTetraS

Summary

Introduction

A basidiomycetous fungus Schizophyllum commune is a common mushroom that is found frequently in the environment, especially on withered trees. Chowdhary reviewed 218 reported cases of basidiomycosis including allergic and invasive mycoses, which showed that the most common causative agent among basidiomycetes was S. commune (52.3%) [2]. S. commune is usually identified by culture methods. Morphological identification of S. commune is difficult, and colonies may be considered contaminated or misidentified as other causative agents because the colony shows non-specific, white, and fluffy characteristics. We previously identified a S. commune antigen Sch c1 [5]. The increased titer against Sch c1 was auxiliary used for the diagnosis of S. commune infection, serum samples are required for the method [6]. Especially non-invasive and rapid options, are being awaited for for the diagnosis of diseases by S. commune

Methods

Results

Conclusion