No abstract

Soil fungal communities involved in the biodegradation of polyester polyurethane (PU) were investigated. PU coupons were buried in two sandy loam soils with different levels of organic carbon: one was acidic (pH 5.5), and the other was more neutral (pH 6.7). After 5 months of burial, the fungal communities on the surface of the PU were compared with the native soil communities using culture-based and molecular techniques. Putative PU-degrading fungi were common in both soils, as <45% of the fungal colonies cleared the colloidal PU dispersion Impranil on solid medium. Denaturing gradient gel electrophoresis showed that fungal communities on the PU were less diverse than in the soil, and only a few species in the PU communities were detectable in the soil, indicating that only a small subset of the soil fungal communities colonized the PU. Soil type influenced the composition of the PU fungal communities. Geomyces pannorum and a Phoma sp. were the dominant species recovered by culturing from the PU buried in the acidic and neutral soils, respectively. Both fungi degraded Impranil and represented >80% of cultivable colonies from each plastic. However, PU was highly susceptible to degradation in both soils, losing up to 95% of its tensile strength. Therefore, different fungi are associated with PU degradation in different soils but the physical process is independent of soil type.The worldwide production of synthetic polymers continues to rise, resulting in an increased environmental burden through the generation of plastic waste. More than 140 million tonnes of plastic was produced worldwide in 2001 (34), and the proportion of household plastic waste in the average American home increased from 3 to 5% of total waste in 1969 (15) to more than 30% in 1995 (21) and continues to rise. Many plastics are both physically and chemically robust and cause waste management problems (10). However, several families of plastics undergo biodegradation in the environment, and an understanding of how this degradation occurs may aid in the development of strategies to exploit these processes for waste management purposes.Microorganisms are responsible for the majority of plastic degradation (6), and abiotic factors such as photodegradation or hydrolysis play a very minor role (18,42). Plastics vulnerable to biodegradation include the polyhydroxyalkanoates, polycaprolactone, polylactic acid, polyvinyl chloride (31, 32), and polyester polyurethane (PU). PU is used in a variety of industrial applications, including insulating foams, fibers, and synthetic leather and rubber goods. The presence of ester and urethane linkages in the backbone of PUs makes them susceptible to hydrolysis by enzymes secreted by microorganisms, releasing breakdown products which may act as a carbon source and lead to a weakening of the tensile strength (1,13,22,26,27).Both PU-degrading fungi (5,6,12,32) and bacteria (1, 20, 23) have been isolated from PU, indicating that there are potential reservoirs of PU-degrading organisms widespread in the environment. It...

a b s t r a c tThe identification and annotation of protein-coding genes is one of the primary goals of whole-genome sequencing projects, and the accuracy of predicting the primary protein products of gene expression is vital to the interpretation of the available data and the design of downstream functional applications. Nevertheless, the comprehensive annotation of eukaryotic genomes remains a considerable challenge. Many genomes submitted to public databases, including those of major model organisms, contain significant numbers of wrong and incomplete gene predictions. We present a community-based reannotation of the Aspergillus nidulans genome with the primary goal of increasing the number and quality of protein functional assignments through the careful review of experts in the field of fungal biology.

Multiple Aspergillus fumigatus isolates from a patient with two aspergillomas complicating chronic pulmonary aspergillosis were pan-azole resistant. Microsatellite typing was identical for all isolates despite major phenotypic and some growth rate differences. Three different cyp51A mutations were found (G138C, Y431C, and G434C), of which the first two were demonstrated by heterologous expression in a hypersusceptible Saccharomyces cerevisiae strain to be at least partly responsible for elevated MICs. cyp51A and cyp51B gene duplication was excluded, but increased expression of cyp51A was demonstrated in three isolates selected for additional study (7-to 13-fold increases). In the isolate with the greatest cyp51A expression, an

Background: Fungi can undergo autophagic-or apoptotic-type programmed cell death (PCD) on exposure to antifungal agents, developmental signals, and stress factors. Filamentous fungi can also exhibit a form of cell death called heterokaryon incompatibility (HI) triggered by fusion between two genetically incompatible individuals. With the availability of recently sequenced genomes of Aspergillus fumigatus and several related species, we were able to define putative components of fungi-specific death pathways and the ancestral core apoptotic machinery shared by all fungi and metazoa.