Caracterización morfológica y molecular de hongos queratinofílicos: el orden onygenales.

Identificador:  TDX:491

Handle:  https://hdl.handle.net/20.500.11797/TDX491

Autors:  Solé Ollé, Maria

Resum:
The order Onygenales is one of the most interesting fungal groups. These fungi are included in the Ascomycetes and contains a number of extremely important fungal pathogens as well as several opportunistic fungi. Onygenales can be frequently found on keratinous substrates. The ability for breakdown the keratin is unusually in there fungi. This ability is very important in the cycle of organic mater because keratin is an important natural material occurring in nature mainly in the form of hair, feather, nails, etc. These fungi therefore play a significant role in the decomposition of soil debris. Any fungus which can produce enzymes capable of decomposing keratinised structures must be regarded as keratinophilic. When the pathogenic strains find a suitable host in favourable conditions , they produce the symptoms of what is know as ringworm diseases. The heterogeneity of the traditional morphological taxonomy of the order make necessary a study for proposing a more natural classification. Currently there are molecular methods, which allow phylogenetic relationships among the different taxa grouped in this order. We performed sequence analysis based on the sequences of the ribosomal internal transcribed spacer (ITS) region and the intervening 5.8S rDNA gene. We have performed a morphological and molecular characterization of these group of fungi based mainly in those genera and species with confused taxonomy.These studies were performed with strains from different international collections and others isolated from soil samples of different origins. For the isolation of fungi from soil samples we have used the hair habit technique described for Vanbreuseghem 1952.We have proposed the following new genera, species and new combinations: New combinations:- Auxarthron kuehnii