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The filamentous fungus Scedosporium prolificans is an emerging multidrug resistant pathogen related to serious infections mainly affecting immunocompromised individuals. Considering that it is frequently isolated from anthropic environments and penetrates mainly through the airways, the human mucosal immune system may play an important protective role against S. prolificans. To advance in the search for biomarkers and targets both for diagnosis and treatment, we analysed the S. prolificans immunomes recognized by human salivary Immunoglobulin A. Using indirect immunofluorescence, it was observed that conidia were strongly recognized, while hyphae were not. By 2-D immunoblotting and peptide mass fingerprinting, 25 immunodominant antigens in conidia and 30 in hyphae were identified. These included catalase, putative glyceronetransferase, translation elongation factor-1α, serine/threonine protein kinase, putative superoxide dismutase, putative mitochondrial cyclophilin 1 and peptidyl-prolyl cis-trans isomerase in conidiospores, and putative Hsp60, ATP synthase β chain, 40S ribosomal protein S0, citrate synthase and putative ATP synthase in hyphae. The functional study showed that metabolism - and protein fate - related enzymes were the most abundant antigens in conidia, whereas metabolism - , translation - , or energy production - related enzymes were in hyphae. The immunogenic proteins identified are proposed as candidates for the development of novel diagnostic tools or therapeutic strategies.

Resumen El Chacoli de Vizcaya/Bizkaiko Txakolina es un vino blanco caracteristico del Pais Vasco con denominacion de origen (BOPV 14/6/94). El objetivo del presente estudio fue seleccionar cepas de levaduras autoctonas para mejorar las condiciones de elaboracion manteniendo las caracteristicas propias de los vinos de esta region. Se aislaron levaduras identificadas como Saccharomyces bayanus durante las campanas 1996-1998 y se sometieron a un proceso selectivo en funcion de sus caracteristicas enologicas y su comportamiento fermentativo. Tres de las cepas seleccionadas se inocularon a escala de bodega sobre mostos monovarietales de las dos variedades de uva aceptadas en esta denominacion de origen, Hondarrabi Zuri y Folle Blanche. La implantacion de las cepas inoculadas en las respectivas vinificaciones fue controlada mediante el analisis del polimorfismo de restriccion del ADN mitocondrial (REAmt) con la enzima AluI, dada su especificidad, rapidez y sencillez tecnologica en comparacion con otras tecnicas de tipificacion molecular utilizadas tambien en este estudio: cariotipificacion cromosomica mediante electroforesis en campo pulsado, Random Amplified Polymorphic DNA-PCR (RAPD-PCR) y analisis del polimorfismo de restriccion originado por la enzima SfiI de corte infrecuente (REA infrecuente). Este estudio ha demostrado que cepas con comportamientos fenotipicos diferentes presentan los mismos patrones de restriccion con REAmt, pero pueden ser diferenciadas con otras tecnicas aplicadas en este estudio, como RAPD-PCR, que pese a su baja reproducibilidad puede ser una herramienta complementaria a REAmt. Nuestros resultados demuestran que, a pesar de utilizar cepas autoctonas seleccionadas, la inoculacion de un caldo con una cepa no es garantia de que domine y dirija la fermentacion del mosto, ya que una misma cepa puede imponerse o no dependiendo del tipo de mosto y de la campana de que se trate. De las levaduras estudiadas, la cepa 2 fue la que mejores resultados proporciono tanto en cata como en implantacion, por lo que podria ser utilizada para la produccion de Chacoli de Vizcaya con fines comerciales, sobre todo de mostos procedentes de Folle Blanche.

Moragues, M. D., Estevez, J. J., Rementeria, A., and Sevilla, M. J. 1994. Effect of n -alkanols on acidification curves of Aureobasidium pullulans suspensions. Experimental Mycology 18, 1-6. n -Alkanols, from methanol to 1-hexanol, induce yeast-to-hyphae transition in the dimorphic fungus Aureobasidium pullulans . In order to elucidate whether triggering of the morphogenetic event is membrane related, we have studied the effect of the morphogenetic n -alkanols on the pH of suspensions of A. pullulans , with no external carbon source. n -Alkanols, at their hyphal inducing concentration or higher, caused a decrease in the initial acidification rate ( C ) of yeast-phase cell suspensions of A. pullulans . From this effect on C , an inhibition coefficient ( K ) was deduced, specific for each alcohol. These coefficients were directly related to the lipid/buffer partition coefficients of the alkanols. On the other hand, germ tubes of A. pullulans , obtained in the presence of n -propanol, showed a much slower acidification rate in water than yeast cells. Moreover, 1-propanol or 1-butanol did not significantly affect the initial acidification rate of germ tubes. The latter observation was interpreted as an adaptation of cells grown in the presence of alcohol. The results of all these experiments support our hypothesis that the plasma membrane is a target of the morphogenetic effects of n -alkanols.