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Knowledge of associations between fungal hosts and their bacterial associates has steadily grown in recent years as the number and diversity of examinations have increased, but current knowledge is predominantly limited to a small number of fungal taxa and bacterial partners. Here, we screened for potential bacterial associates in over 700 phylogenetically diverse fungal isolates, representing 366 genera, or a tenfold increase compared with previously examined fungal genera, including isolates from several previously unexplored phyla. Both a 16 S rDNA-based exploration of fungal isolates from four distinct culture collections spanning North America, South America and Europe, and a bioinformatic screen for bacterial-specific sequences within fungal genome sequencing projects, revealed that a surprisingly diverse array of bacterial associates are frequently found in otherwise axenic fungal cultures. We demonstrate that bacterial associations with diverse fungal hosts appear to be the rule, rather than the exception, and deserve increased consideration in microbiome studies and in examinations of microbial interactions.

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ABSTRACT We report the case of a 25-year-old female patient having a large lesion in the right breast. The core biopsy revealed a high-grade fusocellular neoplasm. Immunostains show no evidence of a specific line of differentiation. The patient underwent radical surgery and adjuvant treatment. Due to the immunohistochemical profile and the rosette arrangement in fusocellular injury, a molecular evaluation of translocations associated to the Ewing sarcoma (ES) was made. However, translocations commonly associated with this disease [t(11;22)(q24;q12)] were not observed. The present report can contribute to the diagnostic investigation of similar cases and to the pre-test orientation of the molecular evaluation.

RESUMEN Presentamos el caso de una paciente de 25 años con lesión voluminosa en mama derecha. La biopsia de la lesión mostró neoplasia fusocelular de alto grado; la inmunohistoquímica no ha determinado la histogénesis de la lesión. La paciente fue sometida a la cirugía radical y al tratamiento adyuvante. Ante el perfil inmunohistoquímico y la formación en roseta de la lesión fusocelular, se ha realizado una evaluación molecular de translocaciones asociadas al sarcoma de Ewing (SE); sin embargo no han sido observadas translocaciones comúnmente asociadas a esa patología [t(11;22)(q24;q12)]. El presente reporte puede ayudar en la investigación diagnóstica en casos similares así como orientar la evaluación molecular.

RESUMO Relatamos o caso de uma paciente, 25 anos de idade, portadora de lesão volumosa em mama direita. A biópsia da lesão evidenciou neoplasia fusocelular de alto grau; a imuno-histoquímica não revelou a histogênese da lesão. A paciente foi submetida à cirurgia radical e ao tratamento adjuvante. Diante do perfil imuno-histoquímico e do arranjo em roseta em lesão fusocelular, foi realizada avaliação molecular de translocações associadas ao sarcoma de Ewing (SE); entretanto não foram observadas translocações comumente associadas a essa patologia [t(11;22)(q24;q12)]. O presente relato pode contribuir para a investigação diagnóstica de casos semelhantes, bem como para a orientação pré-teste da avaliação molecular.

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Sorghum is the fifth most cultivated and consumed grain in the world. However, this grain is frequently contaminated with toxins from fungi. The present study evaluated the effects of environmental factors on tenuazonic acid (TeA) production by Epicoccum sorghinum in the field and in controlled laboratory conditions. In this study, 50 sorghum grain samples were collected from summer and autumn growing seasons and analyzed for TeA contamination using LC-MS/MS. To further understand the ecophysiology of this fungus, an isolated strain of E. sorghinum from the field was investigated for its development and TeA production under controlled environmental conditions in the laboratory. In the ecophysiological investigation, the effects of water activity (0.90, 0.95, 0.99) and temperature (18, 22, 26 and 30 °C) were evaluated on the radial growth, enzymatic production and expression of TAS1, which is the gene involved in TeA production. Results showed that in the field, the summer season presented the highest TeA average level in the grains (587.8 µg/kg) compared to level found in the autumn (440.5 µg/kg). The ecophysiological investigation confirmed that E. sorghinum produces more actively TeA under environmental conditions simulating the summer season. Optimum growth, maximum TAS1 gene expression, and higher extracellular enzymatic production were observed at 26 °C with a water activity of 0.99. Pearson correlation analyses showed that the production of TeA highly correlates with fungal growth. The present study demonstrates that abiotic factors in a combined approach of field and laboratory conditions will assist in predicting the driving environmental factors that could affect growth of E. sorghinum and TeA production in sorghum grains.

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The facultative plant pathogen Epicoccum sorghinum is associated with grain mold of sorghum and produces the mycotoxin tenuazonic acid. This fungus can have serious economic impact on sorghum production. Here, we report the draft genome sequence of E. sorghinum (USPMTOX48).

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The genera Exiguobacterium and Psychrobacter have been frequently detected in and isolated from polar permafrost and ice. These two genera have members that can grow at temperatures as low as -5 and -10 degrees C, respectively. We used quantitative PCR (Q-PCR) to quantify members of these genera in 54 soil or sediment samples from polar, temperate and tropical environments to determine to what extent they are selected by cold environments. These results were further analyzed by multiple linear regression to identify the most relevant environmental factors corresponding to their distribution. Exiguobacterium was detected in all three climatic zones at similar densities, but was patchier in the temperate and tropical samples. Psychrobacter was present in almost all polar samples, was at highest densities in Antarctica sediment samples, but was in very low densities and infrequently detected in temperate and tropical soils. Clone libraries, specific for the 16S rRNA gene for each genus, were constructed from a sample from each climatic region. The clone libraries were analyzed for alpha and beta diversities, as well as for variation in population structure by using analysis of molecular variance. Results confirm that both genera were found in all three climatic zones; however, Psychrobacter populations seemed to be much more diverse than Exiguobacterium in all three climatic zones. Furthermore, Psychrobacter populations from Antarctica are different from those in Michigan and Puerto Rico, which are similar to each other.

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Volatile compound biodegradation analysis usually requires the time-consuming step of extraction of the analytes from the matrix using organic solvents or costly radioactive-compounds. Thus, it is desirable to have a simple and fast technique to generate a good evaluation of bacterial biodegradation. The goal of this research was to develop a methodology on the basis of static headspace-gas chromatography/mass spectrometry (HS-GC/MS) to evaluate the level of volatile contaminant biodegradation. The effects of the following parameters were studied: temperature and time of equilibration. The biodegradation experiments were carried out with bacteria inoculation in mineral media in presence of volatile hydrocarbon compounds (toluene, p-xylene, nonane and naphthalene). Autoclaved inoculates were used as control and reference sample. The optimal headspace conditions were observed when the vials were heated at 80 degrees C for 20 min, the syringe at 81 degrees C and an injection volume of 0.4 mL was used. This methodology has the advantage of being relative free from matrix effects.

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