title: Analytical isoelectric focusing of secreted dermatophyte proteins applied to taxonomic differentiation of Microsporum and Trichophyton species (preliminary studies).
abstract: Culture filtrates were prepared from dermatophytes under standard conditions and adapted for analytical isoelectric focusing in thin layer polyacrylamide gels over the pH range 3.5-9.5. Dermatophytes grown in trypticase soy broth secreted a large number of proteins displaying a wide range of isoelectric points (pIs). Trichophyton megninii extracts contained a triplet of proteins focusing in the pH 8.0-8.5 range that were absent in taxonomically related T. kuryangei isolates. Single ascospore isolates and standard tester strains of Nannizzia otae (+) mating type were differentiated from the (-) mating type by proteins focusing at pH 6.5 and 8.4. These were markedly reduced in the (+) type. The isofocused pattern of Microsporum canis conformed closely to the (-) mating type of N. otae. The protein patterns of T. megninii and T. kuryangei were distinct from those obtained with M. canis and M. equinum because of an intense-staining broad protein band, pI 7.2, and three periodic acid-Schiff-positive glycoproteins focusing in the acidic range which were absent in the Microsporum species. A characteristic protein or doublet (pI 8.7) was present in the Microsporum species and absent in the Trichophyton species. Analytical isoelectric focusing is a potentially useful method to distinguish inter- and intra-species differences in the pattern of secreted dermatophyte proteins present in culture filtrates and in trichophytins. The information derived may be useful in the classification of species.
mesh_terms: D003470:Culture Media; D005656:Fungal Proteins / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D008864:Microsporum / Q000032:analysis / Q000145:classification*; D013045:Species Specificity; D014249:Trichophyton / Q000032:analysis / Q000145:classification*
chemical_list: D003470:Culture Media; D005656:Fungal Proteins