A newly proposed taxonomy of Trichophyton mentagrophytes and related species was introduced and verified with the grounds for the new classification, phylogenetic analysis, and Templeton's cohesive species concept. So-called asexual species were shown to retain sexual ability and different host preferences were shown not to be comparable to different ecological niches. We showed that genealogical concordance phylogenetic species recognition (GCPSR) can be applied to so-called asexual Trichophyton species. The results of GCPSR analysis and mating experiments demonstrated that Arthroderma simii, A. vanbreuseghemii, T. mentagrophytes var. interdigitale, and T. tonsurans may be considered as single phylogenetic species, and that A. benhamiae, T. concentricum, T. verrucosum, and T. mentagrophytes var. erinacei may also be considered as single phylogenetic species. In addition, the conspecificity of three Arthroderma species may also be demonstrated in future. In conclusion, we should not hastily revise the nomenclature based on the phylogenetic tree from only one gene, because different genes can yield different phylogenetic trees. Therefore, we recommend retaining the previous taxonomy until an acceptable taxonomy is proposed.
Genotype characteristics and distribution of commensal Candida albicans should be studied to predict the development of candidiasis, however, extensive genotype analysis of commensal C. albicans has not been made. In this study, 508 C. albicans isolates were collected from patients with/without candidiasis and divided into 4 isolate groups (SG-1, oral cavity of non-candidiasis patients; SG-2, patients with cutaneous candidiasis; SG-3, patients with vaginal candidiasis; SG-4, patients with candidemia). These isolates were characterized to study the relationship between genotypes and pathogenicity using microsatellite analysis. Using CDC3 and CAI, 5 genotypes (I, 111: 115/33: 41; II, 115: 119/23: 23; III, 115: 123/18: 27; IV, 115: 123/33: 40; and V, 123: 127/32: 41) were found in 4.2%, 8.9%, 7.1%, 2.2% and 3.1% of the isolates, respectively. Genotypes II and III were commonly found in all isolate groups. These genotypes were further divided into 28 types by additional HIS3 and CAIII microsatellite markers. In this analysis, C. albicans with type 6 and type 23 was widely distributed as a commensal species in the oral cavity of non-candidiasis patients and found to be related with candidiasis development. Additionally, genotypes I and IV were found in SG-2 and/or SG-4, suggesting that the fungus with those genotypes is also involved in this development. In contrast, genotype V was not identified in any infective isolates.