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The family Ajellomycetaceae (Onygenales) includes mammal-associated pathogens within the genera Blastomyces, Emmonsia, Histoplasma and Paracoccidioides, as well as the recently described genera, Emergomyces that causes disease in immunocompromised hosts, and Emmonsiellopsis, known only from soil. To further assess the phylogenetic relationships among and between members of these genera and several previously undescribed species, we sequenced and analyzed the DNA-directed RNA polymerase II (rPB2), translation elongation factor 3-α (TEF3), β-tubulin (TUB2), 28S large subunit rDNA (LSU) and the internal transcribed spacer regions (ITS) in 68 strains, in addition to morphological and physiological investigations. To better understand the thermal dimorphism among these fungi, the dynamic process of transformation from mycelial to yeast-like or adiaspore-like forms was also assessed over a range of temperatures (6-42 °C). Molecular data resolved the relationships and recognized five major well-supported lineages that correspond largely to the genus level. Emmonsia, typified by Emmonsia parva, is a synonym of Blastomyces that also accommodates Blastomyces helicus (formerly Emmonsia helica). Emmonsia crescens is phylogenetically distinct, and found closely related to a single strain from soil without known etiology. Blastomyces silverae, Emergomyces canadensis, Emergomyces europaeus and Emmonsia sola are newly described. Almost all of the taxa are associated with human and animal disease. Emmonsia crescens, B. dermatitidis and B. parvus are prevalently associated with pulmonary disease in humans or animals. Blastomyces helicus, B. percursus, Emergomyces africanus, Es. canadensis, Es. europaeus, Es. orientalis and Es. pasteurianus (formerly Emmonsia pasteuriana) are predominantly found in human hosts with immune disorders; no animal hosts are known for these species except B. helicus. [ABSTRACT FROM AUTHOR]

Mycoleptodiscus indicus is a recognized plant pathogen which has very rarely been reported as a cause of human infection. It is a tropical or subtropical fungus which is difficult to culture and identify from clinical specimens. This is the first report of septic arthritis with this fungus in a healthy Canadian male. The fungal infection was contracted on a vacation in Costa Rica, probably through direct inoculation through injured skin. The fungus was isolated from synovial fluid and identification was confirmed by DNA sequencing. There has only been one previous case of septic arthritis of the knee and one skin infection reported with this fungus; both cases involved immunocompromised hosts. Both septic arthritis patients required joint surgery and lavage to eradicate the fungus, however, only the immunocompromised patient required antifungal medications. In the future, it is very likely that the number of patients identified with M. indicus infection will rise due to increasing awareness of this pathogen as well as increasing exposure. Many immunocompromised patients on anti-retroviral or biologic therapy are healthy enough to travel, thereby exposing themselves to exotic and infected plants which increase the risk of unusual fungal infections. [ABSTRACT FROM AUTHOR]

In 1969, specialists at the Kananaskis hyphomycete workshop coined the terms 'blastic' and 'thallic' to describe two distinct modes of conidiogenesis. Since then, the original concepts have been slightly modified and redefined, and the terms have been widely adopted in taxonomic descriptions of conidial fungi. Problems arise in the application of these terms to conidial development in fungi which demonstrate morphological plasticity ranging from fragmentation of a hypha to extrusion of a portion of a hypha or cell. A number of fungi, such as anamorphs of Onygenales which includes many of the fungi pathogenic to man, demonstrate intergradations between blastic and thallic development. Because development in this group of fungi is difficult to categorize, it has led to an inconsistent treatment of taxa which share many other developmental features in common. In using these terms, it should be remembered that they represent extremes in a developmental spectrum. [ABSTRACT FROM AUTHOR]

Characterization of microorganisms associated with alfalfa leaf-cutter bee ( Megachile rotundata) nectar, pollen, provisions, larval guts, and frass (excreta) in Alberta demonstrated a varied aerobic microflora. Yeasts were isolated frequently from nectar, pollen, and provisions but rarely from guts or frass. The most prevalent yeast taxa were: Candida bombicola, Cryptococcus albidus, Metschnikowia reukaufii, and Rhodotorula glutinis. Although few filamentous fungi were found in nectar, they were frequently isolated from pollen and provisions; the predominant taxa were Alternaria alternata, Cladosporium cladosporioides, C. herbarum, Epicoccum nigrum, and Penicillium chrysogenum. Bacteria, including species of Bacillus, Corynebacterium, Micrococcus, and the actinomycete Streptomyces, also were prevalent in provisions and/or on pollen. In general, the diversity of microorganisms isolated from alimentary canals and frass was lower than from nectar, pollen, and provisions. Bacillus firmus, B. licheniformis, B. megaterium, B. pumilus, and Streptomyces spp. were the most frequently isolated bacteria, whereas Trichosporonoides megachiliensis was the most common filamentous fungus isolated from larval guts and/or frass. These taxa may be part of the resident microflora of the alimentary canal. Populations of bacteria and filamentous fungi, but not yeasts, were larger from Ascosphaera aggregata-infected larvae than from healthy larvae. However, with the exception of Aspergillus niger and T. megachiliensis in frass from healthy larvae, no taxon of filamentous fungi was conspicuously present or absent in infected larvae, healthy larvae, or their frass. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

Members of the genus Nannizziopsis are emerging fungal pathogens of reptiles that have been documented as the cause of fatal mycoses in a wide range of reptiles in captivity. Cases of severe, proliferative dermatitis, debility and death have been detected in multiple free-living lizard species from locations across Australia, including a substantial outbreak among Eastern water dragons (Intellagama lesueurii) in Brisbane, Queensland. We investigated this disease in a subset of severely affected lizards and identified a clinically consistent syndrome characterized by hyperkeratosis, epidermal hyperplasia, dermal inflammation, necrosis, ulceration, and emaciation. Using a novel fungal isolation method, histopathology, and molecular techniques, we identified the etiologic agent as Nannizziopsis barbatae, a species reported only once previously from captive lizards in Australia. Here we report severe dermatomycosis caused by N. barbatae in five species of Australian lizard, representing the first cases of Nannizziopsis infection among free-living reptiles, globally. Further, we evaluate key pathogen and host characteristics that indicate N. barbatae-associated dermatomycosis may pose a concerning threat to Australian lizards. [ABSTRACT FROM AUTHOR]