Analysis of a polygalacturonase gene of Ustilago maydis and characterization of the encoded enzyme.

Ustilago maydis is a pathogenic fungus that produces the corn smut. It is a biotrophic parasite that depends on living plant tissues for its proliferation and development. Polygalacturonases are secreted by pathogens to solubilize the plant cell-wall and are required for pathogen virulence.

Molecular identification of two strains of Cercospora rodmanii isolated from water hyacinth present in Yuriria lagoon, Guanajuato, Mexico and identification of new hosts for several other strains.

Water hyacinth is a beautiful monocotyledon plant that has been dispersed all over the world by humans. The plant has been present in Mexico since 1907, and many water bodies have become infested with it since then. In 2001, we initiated a survey in Yuriria lagoon in southern Guanajuato state to isolate fungi able to biocontrol the plant.

Intracellular distribution of fatty alcohol oxidase activity in Mucor circinelloides YR-1 isolated from petroleum contaminated soils.

In previous studies, Mucor circinelloides YR-1 isolated from petroleum-contaminated soils grown in decane as sole carbon source, showed fatty alcohol oxidase (FAO) activities in either particulate or soluble fractions from a cell-free extract. One is associated to internal membranes (mFAO) and the other one is soluble (sFAO). Both activities appear to be located in the cells in specific compartments other than peroxisomes.

Biosynthesis of glycoproteins in the human pathogenic fungus Sporothrix schenckii: synthesis of dolichol phosphate mannose and mannoproteins by membrane-bound and solubilized mannosyl transferases.

A membrane fraction obtained from the filamentous form of Sporothrix schenckii was able to transfer mannose from GDP-Mannose into dolichol phosphate mannose and from this inTermediate into mannoproteins in coupled reactions catalyzed by dolichol phosphate mannose synthase and protein mannosyl transferase(s), respectively. Although the transfer reaction depended on exogenous dolichol monophosphate, membranes failed to use exogenous dolichol phosphate mannose for protein mannosylation to a substantial extent. Over 95% of the sugar was transferred to proteins via dolichol phosphate mannose and the reaction was stimulated several fold by Mg2+ and Mn2+.

The properties and localization of Saprolegnia monoica chitin synthase differ from those of other fungi.

The presence of non-fibrillar alpha-chitin in cellulosic fungi (class Oomycetes) poses intriguing questions as to its role, subcellular localization and evolutionary significance. Previous studies reported on the similarity of chitin synthase from Saprolegnia monoica with that of other fungi. The present work describes important dissimilarities.