Microsatellite-Primed PCR for Intra-species Genetic Relatedness in Trichophyton ajelloi Strains Isolated in Poland from Various Soil Samples

Trichophyton ajelloi is a geophilic dermatophyte that specializes in the decomposition of native keratin. It exists in soil with a permanent influx of keratin matter. In the present study, two PCR-based methods were used for the identification and intra-species differentiation of T. ajelloi strains isolated from 3 types of soils with different physicochemical properties. The first method, employed for molecular identification, was PCR amplification of the 5.8S rRNA gene and its flanking regions encoding internal transcribed spacers (ITSs), followed by restriction enzyme digestion using endonuclease HinfI. The second method, employed for molecular differentiation, was microsatellite-primed PCR (MSP-PCR) using the repetitive oligonucleotide (GACA)4. All the T. ajelloi strains were also identified using a traditional culture method. Our results showed that molecular identification using the PCR-restriction fragment length polymorphism (PCR-RFLP) method agreed with the identification made using the traditional approach. On the other hand, PCR-RFLP results showed no strain differentiation, while MSP-PCR using the (GACA)4 primer identified different varieties among the T. ajelloi strains. The reasons for the intra-species differentiation of T. ajelloi have been discussed.