Common mechanism of recognition and binding of the complementary molecules, carbohydrate-lectin, in the verticillium disease of Agaricus bisporus and Pleurotus ostreatus cultivated mushrooms

Se compara la interacción carbohidrato-lectina entre el glucogalactomananoaislado de las paredes celulares de Verticillium fungicola y las lectinas de los carpóforosde Agaricus bisporus o de Pleurotus ostreatus, para establecer el mecanismomolecular de la «mole seca» o verticiliosis de los cultivos comerciales de ambassetas comestibles. La interacción entre las moléculas complementarias, «moléculasdiana», parece ser debida a la galactosa terminal unida en (1-4) al esqueleto demanosa unido en (1-6) de la molécula del glucogalactomanano de V. fungicola

The carbohydrate-lectin interaction between the isolated glucogalactomannanof Verticillium fungicola cell walls, and lectins, either from Agaricus bisporus orPleurotus ostreatus fruit bodies, was compared in order to establish the molecularmechanism of the «dry bubble» or verticillium disease exhibited in the commercialcultures of both edible mushrooms. This interaction between complementarymolecules, «target molecules», appears to be due to the terminal galactose linkedat (1-4) to the (1-6) mannose bone of the V. fungicola glucogalactomannan molecule

Comparative effect of the fungicide Prochloraz-Mnon Agaricus bisporus vegetative-mycelium and fruit-body cell walls / Estudios comparativos del efecto del fungicida Prochloraz-Mn sobre las paredes celulares del micelio vegetativo y de los cuerpos fructíferos de Agaricus bisporus

Fungicides to control mycopathogens of commercial Agaricus bisporus, a mushroom cultivated for human consumption, are a major field of study, since these chemicals are toxic to both the host and its fungal parasites. The fungicide Prochloraz-Mn, used at its LD50 for A. bisporus, partially inhibited protein biosynthesis in the vegetative my celial cell walls of this mushroom and caused significant changes in cell-wall polysaccharide structure, as deduced by methylation analysis and gas liquid chromatography-mass spectrometry (GLC-MS).Furthermore, the aggregated my celial walls showed distinct alterations in their overall chemical composition following the administration of Prochloraz-Mn at the LD50 and the LD50 ×1000. As expected, GLC-MS studies indicated that the latter dose caused more appreciable differences in polysaccharide structure. The decrease in mushroom crop yields obtained from industrial cultures treated with Prochloraz-Mn to control V. fungicola infection depended on the dose of the fungicide employed, whereas fruit-body morphology was only slightly affected at the highest Prochloraz-Mn concentration used (AU)

Los fungicidas para el control de micopatógenos de Agaricusbisporus, un hongo de cultivo comercial para consumo humano, representan un importante tema de estudio debido a que son tóxicos tanto para el huésped como para sus parásitos fúngicos. El fungicida Prochloraz-Mn, empleado a su LD50 para A. bisporus, inhibe parcialmente la biosíntesis de proteínas en las pared celular del micelio vegetativo de este hongo y provoca cambios significativos en la estructura polisacárida de la pared celular, tal como se observa mediante el análisis de metilación y la cromatografía líquida de gases-espectrometría de masa (GLC-MS). Además, las paredes agregadas del micelio presentan diferentes alteraciones en la composición química global después de la administración de Prochloraz-Mn a la LD50 y LD50×1000. Como cabría esperar, los estudios de GLC-MS, indican que la última dosis causa más diferencias apreciables en la estructura polisacárida. La disminución en la producción del hongo en los cultivos industriales tratados con Prochloraz-Mn para controlar la infección por V. fungicola, dependía de la dosis de fungicida empleada, mientras que la morfología del cuerpo fructífero sólo resulta ligeramente afectada a la concentración de Prochloraz-Mnmás elevada (AU)

Comparative effect of the fungicide Prochloraz-Mn on Agaricus bisporus vegetative-mycelium and fruit-body cell walls.

Fungicides to control mycopathogens of commercial Agaricus bisporus, a mushroom cultivated for human consumption, are a major field of study, since these chemicals are toxic to both the host and its fungal parasites. The fungicide Prochloraz-Mn, used at its LD50 for A. bisporus, partially inhibited protein biosynthesis in the vegetative mycelial cell walls of this mushroom and caused significant changes in cell-wall polysaccharide structure, as deduced by methylation analysis and gas liquid chromatography-mass spectrometry (GLC-MS). Furthermore, the aggregated mycelial walls showed distinct alterations in their overall chemical composition following the administration of Prochloraz-Mn at the LD50 and the LD50 x1000. As expected, GLC-MS studies indicated that the latter dose caused more appreciable differences in polysaccharide structure. The decrease in mushroom crop yields obtained from industrial cultures treated with Prochloraz-Mn to control V. fungicola infection depended on the dose of the fungicide employed, whereas fruit-body morphology was only slightly affected at the highest Prochloraz-Mn concentration used.