OBJECTIVETo observe the unique DNA profile and the relationship between DNA profile and phenotype of Trichophyton rubrum,and establish an effective molecular method to identify T. rubrum.

METHODSThree primers, including (GACA)(4), (GTG)(5) and M13 core sequence (5'-GAGGGTG-GCGGTTCT-3'), were used to distinguish variations among 20 clinical isolates of T. rubrum and Trichophyton mentagrophytes.

RESULTSDifferent PCR-fingerprinting was seen between T. rubrum and T. mentagrophytes using three different primers. 2 stains of T. rubrum were identified among 6 supposed T. mentagrophytes.

CONCLUSIONST. rubrum can be distinguished using PCR, and (GACA)(4) is the most suitable primer.

DNA Fingerprinting ; methods ; Humans ; Polymerase Chain Reaction ; methods ; Trichophyton ; genetics ; isolation & purification

BACKGROUND: The identification of molds in clinical laboratories is largely on the basis of phenotypic criteria, the classification of which can be subjective. Recently, molecular methods have been introduced for identification of pathogenic molds in clinical settings. Here, we employed comparative sequence analysis to identify molds. METHODS: A total of 47 clinical mold isolates were used in this study, including Aspergillus and Trichophyton. All isolates were identified by phenotypic properties, such as growth rate, colony morphology, and reproductive structures. PCR and direct sequencing, targeting the internal transcribed spacer (ITS) region, the D1/D2 region of the 28S subunit, and the beta-tubulin gene, were performed using primers described previously. Comparative sequence analysis by using the GenBank database was performed with the basic local alignment search tool (BLAST) algorithm. RESULTS: For Aspergillus, 56% and 67% of the isolates were identified to the species level by using ITS and beta-tubulin analysis, respectively. Only D1/D2 analysis was useful for Trichophyton identification, with 100% of isolates being identified to the species level. Performances of ITS and D1/D2 analyses were comparable for species-level identification of molds other than Aspergillus and Trichophyton. In contrast, the efficacy of beta-tubulin analysis was limited to genus identification because of the paucity of database information for this gene. CONCLUSIONS: The molecular methods employed in this study were valuable for mold identification, although the different loci used had variable usefulness, according to mold genus. Thus, a tailored approach is recommended when selecting amplification targets for molecular identification of molds.
Aspergillus/genetics/isolation & purification ; DNA, Fungal/analysis/isolation & purification ; Databases, Genetic ; Fungi/genetics/*isolation & purification ; Humans ; Polymerase Chain Reaction ; RNA, Ribosomal, 28S/*genetics ; Sequence Analysis, DNA ; Trichophyton/genetics/isolation & purification ; Tubulin/*genetics

To find a fast and efficient way of identifying seven common dermatophytes in clinical practice, we used the techniques of polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) targeting Topoisomerase II gene. The DNA of 7 dermatophytes, along with Candida albicans, Aspergillus terreus and Aspergillus flavus were amplified by consensus primer dPsD1. They were then subjected to a second PCR with primers dPsD2 and species-specific primers PsT and PsME separately. 6 of the products generated by dPsD2 were digested with restriction enzyme Hinc II. DNA fragments of 3390 bp and 2380 bp was amplified by using consensus primer dPsD1 and dPsD2 from the genomic DNA of each dermatophyte species separately. By combining the results of the two species-specific primer sets (PsT and PsME), all species of dermatophyte yielded unique sizes-set of PCR products expect for T. mentagrophytes and T. tonsurans. From the restriction profiles of Hinc II, 6 of the 7 dermatophytoses were diagnosed to species level including T. mentagrophytes and T. tonsurans. By combining the results of the PCR and PCR-RFLP, the 7 common dermatophytes can be identified to species level. It is conclude that the multiplex PCR and PCR-RFLP identification targeting the DNA topoisomerase II gene is rapid and efficient.
Arthrodermataceae ; classification ; isolation & purification ; Aspergillus ; isolation & purification ; Candida albicans ; isolation & purification ; DNA Topoisomerases, Type II ; genetics ; Dermatomycoses ; microbiology ; Humans ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Trichophyton ; isolation & purification

To find a fast and efficient way of identifying seven common dermatophytes in clinical practice, we used the techniques of polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) targeting Topoisomerase II gene. The DNA of 7 dermatophytes, along with Candida albicans, Aspergillus terreus and Aspergillus flavus were amplified by consensus primer dPsD1. They were then subjected to a second PCR with primers dPsD2 and species-specific primers PsT and PsME separately. 6 of the products generated by dPsD2 were digested with restriction enzyme Hinc II. DNA fragments of 3390 bp and 2380 bp was amplified by using consensus primer dPsD1 and dPsD2 from the genomic DNA of each dermatophyte species separately. By combining the results of the two species-specific primer sets (PsT and PsME), all species of dermatophyte yielded unique sizes-set of PCR products expect for T. mentagrophytes and T. tonsurans. From the restriction profiles of Hinc II, 6 of the 7 dermatophytoses were diagnosed to species level including T. mentagrophytes and T. tonsurans. By combining the results of the PCR and PCR-RFLP, the 7 common dermatophytes can be identified to species level. It is conclude that the multiplex PCR and PCR-RFLP identification targeting the DNA topoisomerase II gene is rapid and efficient.
Arthrodermataceae/classification ; Arthrodermataceae/*isolation & purification ; Aspergillus/*isolation & purification ; Candida albicans/isolation & purification ; DNA Topoisomerases, Type II/genetics ; Dermatomycoses/microbiology ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Trichophyton/*isolation & purification

This study is to investigate the effect of Euphorbia humifusa effective fraction (EHEF) on the CYP51 enzyme activity, the lanosterol content and the MEP, SUB gene expression of Trichophyton rubrum. Trichophyton rubrum was treated by EHEF for 7 days at 26 degrees C. The activity of CYP51 enzyme of Trichophyton rubrum in the cell membrane was determined by using ELISA kit, and the lanosterol content was investigated by using high performance liquid chromatography (HPLC), and the MEP, SUB gene expression of Trichophyton rubrum was detected with the reverse transcription polymerase chain reaction (RT-PCR) method. Results showed that EHEF can decrease the membrane CYP51 enzyme activity, and it also can accumulate the fungal lanosterol in a dose-dependent manner, and it also can decrease the gene expression of MEP and SUB. The antifungal mechanism of EHEF may be related to the inhibition on CYP51 enzyme activity, and to the effects on fungal cell membrane ergosterol biosynthesis. It may also play an antifungal effect by inhibiting the MEP, SUB gene expression of fungal proteases.
Antifungal Agents ; isolation & purification ; pharmacology ; Cell Membrane ; drug effects ; metabolism ; Drugs, Chinese Herbal ; isolation & purification ; pharmacology ; Enzyme Activation ; drug effects ; Euphorbia ; chemistry ; Gene Expression Regulation, Fungal ; Lanosterol ; metabolism ; Metalloproteases ; metabolism ; Plants, Medicinal ; chemistry ; Sterol 14-Demethylase ; metabolism ; Subtilisins ; metabolism ; Trichophyton ; drug effects ; genetics ; metabolism