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The objective of this study was to isolate and screen the highly efficient copper-removing microorganisms from the petroleum hydrocarbon (PH)-contaminated sites in the Amazonian rain forest in Ecuador. Two bacterial strains (strain UEAB3 and UEAB6) have shown 100% microbial resistance on the nutrient medium containing 100 mM of MgCl2, FeCl3, and Al2(SO4)3 separately. Though these two strains were less tolerant of ZnCl2 and CuSO4.5H2O, they have proven 100% resistance at the lower concentrations of these two metals. According to atomic absorption spectroscopy (AAS) analysis, the filamentous fungi (strains UEAFr and UEAFg) were significantly (p

The fungus Geomyces destructans is the causative agent of white-nose syndrome (WNS), a disease that has killed millions of North American hibernating bats. We describe a real-time TaqMan PCR test that detects DNA from G. destructans by targeting a portion of the multicopy intergenic spacer region of the rRNA gene complex. The test is highly sensitive, consistently detecting as little as 3.3 fg genomic DNA from G. destructans. The real-time PCR test specifically amplified genomic DNA from G. destructans but did not amplify target sequence from 54 closely related fungal isolates (including 43 Geomyces spp. isolates) associated with bats. The test was qualified further by analyzing DNA extracted from 91 bat wing skin samples, and PCR results matched histopathology findings. These data indicate the real-time TaqMan PCR method described herein is a sensitive, specific and rapid test to detect DNA from G. destructans and provides a valuable tool for WNS diagnostics and research.

White nose syndrome, caused by Geomyces destructans, has killed more than 5 million cave hibernating bats in eastern North America. During hibernation, the lack of inflammatory cell recruitment at the site of fungal infection and erosion is consistent with a temperature-induced inhibition of immune cell trafficking. This immune suppression allows G. destructans to colonize and erode the skin of wings, ears and muzzle of bat hosts unchecked. Yet, paradoxically, within weeks of emergence from hibernation an intense neutrophilic inflammatory response to G. destructans is generated, causing severe pathology that can contribute to death. We hypothesize that the sudden reversal of immune suppression in bats upon the return to euthermia leads to a form of immune reconstitution inflammatory syndrome (IRIS). IRIS was first described in HIV-infected humans with low helper T lymphocyte counts and bacterial or fungal opportunistic infections. IRIS is a paradoxical and rapid worsening of symptoms in immune compromised humans upon restoration of immunity in the face of an ongoing infectious process. In humans with HIV, the restoration of adaptive immunity following suppression of HIV replication with anti-retroviral therapy (ART) can trigger severe immune-mediated tissue damage that can result in death. We propose that the sudden restoration of immune responses in bats infected with G. destructans results in an IRIS-like dysregulated immune response that causes the post-emergent pathology.

Two new psychrophilic Pseudogymnoascus species with Geomyces anamorphs are described from a Sphagnum bog in Alberta, Canada. Pseudogymnoascus appendiculatus has long, branched, orange appendages and smooth, fusoid to ellipsoidal ascospores with a faint longitudinal rim. Pseudogymnoascus verrucosus has short, subhyaline appendages and warty peridial hyphae and ascospores, and both smooth to asperulate and irregularly warty conidia. Both species produce asci in chains, a feature that supports the distinction between this group and Myxotrichum, which produces asci singly. The discovery of species intermediate between Pseudogymnoascus and Gymnostellatospora, in having both ornamented ascospores and Geomyces anamorphs, prompted a re-evaluation of the genera. Sequence analysis of the internal transcribed spacer regions (ITS) of the nuclear ribosomal DNA indicates that the two genera remain distinct and comprise a monophyletic group. Pseudogymnoascus species have smooth to warty or lobate-reticulate ascospores while species of Gymnostellatospora have walnut-shaped spores with distinct longitudinal crests and striations. Anamorphs assignable to the form genus Geomyces are allied with both genera. A key is provided to the four species and varieties of Pseudogymnoascus.

In this study, the complete mitochondrial genome of the White-Nose Syndrome pathogen, Pseudogymnoascus destructans (=Geomyces destructans), is sequenced. The circular mitochondrial genome is 32,181 bp long and encodes 13 standard proteins, 2 ribosomal RNA subunits, and 27 tRNAs. The genome contains two introns located within the cytochrome c oxidase subunit 1 gene (cox1) and the large ribosomal RNA subunit (rrnl), with each intron encoding one gene, orf110 and rps3, respectively. Phylogenetic analysis of the concatenated mitochondrial protein-coding genes of P. destructans and close representatives in Leotiomycetes showed that P. destructans was closely related to Pseudogymnoascus pannorum, consistent with nuclear genes.

The effects of growth temperature on soluble carbohydrate and lipid content of Humicola marvinii, Geomyces pannorum and Mortierella elongata isolated from the Antarctic (Signy Island; 60° 43′S, 45°38′W) were investigated. Each of these fungi responded differently to suboptimal growth temperatures. At low temperatures Humicola marvinii accumulated cryoprotective carbohydrates (trehalose intracellularly and glycerol extracellularly), whereas Geomyces pannorum responded by altering its lipid composition with increases in unsaturated lipid content and overall unsaturation index. In the case of Mortierella elongata, features that may influence its ability to grow at low temperatures included the absence of detectable ergosterol, the presence of stearidonic acid and increased amounts of intracellular trehalose when grown at lower temperatures. The relative importance of lipid and carbohydrate metabolism in adaptation to temperature stress in these fungi is discussed.

Soil microfungal communities of two ad- jacent, but differently aged Alnus viridis coenoses were studied using the soil dilution plate method. A total of 84 taxa were isolated: 59 from the young com- munity, 51 from the old and 26 taxa shared. Morti- erella parvispora and Pythium sp. had the highest den- sity values in the young and the old alder community, respectively. Species compositions were compared be- tween plots of the two communities using a metric multidimensional scaling and a correspondence anal- ysis. Both analyses grouped plots from the young and the old community separately, suggesting a correla- tion between the changes in the fungal species com- position and the age of the alder communities. The correspondence analysis produced two species groups more related to one set of plots or the other, together with another group formed of Mortierella, Micromucor, Geomyces and Trichoderma species, whose distributions were more closely related to the general abiotic conditions than the age of the alder com- munities. It is proposed that the significant differ- ences in the composition of the two fungal commu- nities mirror the existence of a seral fungal succes- sion paralleling the aging of the alder communities.

Increased temperature of incubation induces growth in vitro of the parasitic forms of some of the fungi which cause systemic mycoses in man. DeMonbreun observed this phenomenon when he described the growth of Histoplasma capsulatum Darling in vitro on various culture media and under differing conditions of incubation (5). DeMonbreun described also the development in vitro of the yeast form of Blastomyces dermatitids Gilchrist & Stokes when cultures were incubated at 37 C (6). Redaelli and Ciferri reported that the parasitic, multiple-budding form of Paracoccidioides brasiliensis (Splendore) Almeida can be maintained in vitro at 37 C (13). The effects of temperature and other factors upon the morphology of these and other fungal pathogens of man have been reviewed in many papers (3, 4, 10, 11, 12, 14, 15). The most notable features of Emmonsia crescens Emmons & Jellison as it grows in the lungs of animals are its great increase in size (up to 106 increase in volume of the inhaled conidia), the great thickness of the wall (up to 70 /A) and its failure to reproduce in mammalian tissue in any manner. The parasitic form of this fungus can be produced in vitro by incubation of the fungus at 37 C (8). Because of these striking characteristics of E. crescens Emmons and Jellison proposed the name "adiaspore" for the transformed conidium which grows to an enormous size (up to 700 , in diam) in the lung of a naturally or experimentally infected animal without reproducing (8). Because of these unusual features, the generic name proposed by Ciferri and Montemartini (2) is retained in this paper. Carmichael has referred Emmonsia parva (Emmons & Ashburn) Ciferri & Montemartini, E. crescens (which he designated as a variety of E. parva), Blastomyces dermatitidis, Aleurisma spp. and Geomyces spp. to the genus Chrysosporium Corda without attaching sufficient importance to the in vivo behavior of these fungi (1). Chrysosporium spp., as defined by

Two new species of xerophilic fungi are described: Geomyces pulvereus Hocking & Pitt, and Monascus eremophilus Hocking & Pitt. The Monascus species is an obligate xerophile, which does not appear to have an anamorphic state. A further occurrence of Eurotium halophilicum is reported, and a full description of this rarely encountered species is given. During the course of investigations into spoilage of various low water activity (aw) foodstuffs and commodities over several years, three unusual xerophilic fungi were isolated. One was identified as Eurotium halophilicum Christensen et al., a rarely encountered xerophile, and it was concluded that the other isolates belonged to two previously undescribed species. Although one species is represented by only a single isolate, and the other by only two isolates, the new taxa are sufficiently distinctive to warrant description as new species. E. halophilicum has not been reported in the literature since it was described in 1959.