Kazuo Yasuda

The First Isolation of Arthroderma benhamiae in Japan

A clinical isolate of Trichophyton mentagrophytes from rabbit was examined by polymerase chain reaction (PCR) analysis and a mating experiment. The species‐specific primers designed from the nucleotide sequences of the chitin synthase 1 (CHS1) gene in the teleomorph of Arthroderma benhamiae amplified a fragment from genomic DNA samples of A. benhamiae and the clinical isolate but not from those of A. simii and A. vanbreuseghemii. On the other hand, the species‐specific primers of A. simii and A. vanbreuseghemii did not amplify any fragment from the genomic DNA of the clinical isolates. When the isolate was respectively crossed with (+) or (‐) tester strains of A. benhamiae, A. simii and A. vanbreuseghemii, ascospores were produced in the crossing with the A. benhamiae (+) strain. Therefore, the isolate was identified to be A. benhamiae (‐), confirming the result of molecular analysis. This is the first report on the isolation of A. benhamiae in Japan.