Phylogenetic Classification of Trichophyton mentagrophytes Complex Strains Based on DNA Sequences of Nuclear Ribosomal Internal Transcribed Spacer 1 Regions

Abstract

Using internal transcribed spacer 1 (ITS1) region ribosomal DNA sequences from 37 stock strains and clinical isolates provisionally termed Trichophyton mentagrophytes complex in Japan, we demonstrated the mutual phylogenetic relationships of these strains. Members of this complex were classified into 3 ITS1-homologous groups and 13 ITS1-identical groups by their sequences. ITS1-homologous group I consists of Arthroderma vanbreuseghemii, T. mentagrophytes human isolates, and several strains of T. mentagrophytes animal isolates. Five strains of Arthroderma simii form a cluster comprising ITS1-homologous group II. The Americano-European and African races of Arthroderma benhamiae, T. mentagrophytes var. erinacei, and one strain of a T. mentagrophytes animal isolate constitute ITS1-homologous group III. According to the phylogenetic tree constructed with Trichophyton rubrum as an outgroup, ITS1-homologous groups I and II comprised a monophyletic cluster and ITS1-homologous group III constituted another cluster which was rather distant from the others in the complex. This system was applicable to the phylogenetic analysis of closely related strains. Using this technique, human and animal isolates of T. mentagrophytes were also clearly distinguishable from each other.

rRNA Gene Internal Transcribed Spacer 1 and 2 Sequences of Asexual, Anthropophilic Dermatophytes Related to Trichophyton rubrum

“…Sequence analysis also clearly distinguished the partially interfertile American-European and African races of A. benhamiae. This distinction has previously been shown in an ITS1 analysis by Makimura et al (22). A very atypical T. mentagrophytes isolate with red colony reverse coloration and a growth requirement for exogenous inositol, UAMH 7339, clustered very closely to the American-European A. benhamiae but was not identical to A. benhamiae mating tester RV 26680.…”

“…The present study therefore investigated whether a highly variable region of fungal DNA, the ribosomal region consisting of internal transcribed spacer sequences (ITS) 1 and 2 and their intermediary 5.8S rDNA, exhibited adequate variability to resolve the diversity of anthropophilic species and to determine their phylogeny. Some reports in which sequences are given for the ITS1 region of certain dermatophytes have recently appeared, giving broad overviews of dermatophytes (22) and of the T. mentagrophytes complex (23). The present study focused in greater detail on species known or thought to be related to T. rubrum, including some zoophilic lineages that may be ancestral to this common anthropophile.…”

<p>Emergence of Terbinafine Resistant <em>Trichophyton mentagrophytes</em> in Iran, Harboring Mutations in the Squalene Epoxidase (<em>SQLE</em>) Gene</p>

“…Briefly, the isolates were sub-cultured on Sabouraud dextrose agar (SDA; BD Diagnostics, USA) and incubated at 28°C for one week. Genomic DNA was isolated from the mycelium of each strain by mechanical homogenization in lysis buffer, consisting of 200 mM Tris-HCl [pH 8.0], 0.5% sodium dodecyl sulfate, 250 mM NaCl, and 25 mM EDTA 22 with the use of SpeedMill device (Analytik Jena, Germany), followed by purification with phenolchloroform-isoamyl alcohol (25:24:1) and precipitation with ethanol. ITS region was amplified in each isolate by V9G (5′-TTACGTCCCTGCCCTTTGTA-3′) and LS266 (5′-GCATTCCCAAACAACTCGACTC-3′) primers.…”

Development of a Species-Specific PCR-Restriction Fragment Length Polymorphism Analysis Procedure for Identification of Madurella mycetomatis

“…rDNA sequences have been utilized by many investigators for the determination of species identity for a multitude of yeasts and fungi (2,7,10,12,25). It has also been reported that ITS ribotyping is a simple method that can distinguish among most of the Saccharomyces species (17), and ITS sequences can differentiate between the closely related strains in the Trichophyton mentagrophytes complex (16).…”