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Fungi in the order Chaetothyriales are renowned for their ability to cause human infections. Nevertheless, they are not regarded as primary pathogens, but rather as opportunists with a natural habitat in the environment. Extremotolerance is a major trend in the order, but quite different from black yeasts in Capnodiales which focus on endurance, an important additional parameter is advancing toxin management. In the ancestral ecology of rock colonization, the association with metabolite-producing lichens is significant. Ant-association, dealing with pheromones and repellents, is another mainstay in the order. The phylogenetically derived family, Herpotrichiellaceae, shows dual ecology in monoaromatic hydrocarbon assimilation and the ability to cause disease in humans and cold-blooded vertebrates. In this study, data on ecology, phylogeny, and genomics were collected and analyzed in order to support this hypothesis on the evolutionary route of the species of Chaetothyriales. Comparing the ribosomal tree with that of enzymes involved in toluene degradation, a significant expansion of cytochromes is observed and the toluene catabolism is found to be complete in some of the Herpotrichiellaceae. This might enhance human systemic infection. However, since most species have to be traumatically inoculated in order to cause disease, their invasive potential is categorized as opportunism. Only in chromoblastomycosis, true pathogenicity might be surmised. The criterion would be the possible escape of agents of vertebrate disease from the host, enabling dispersal of adapted genotypes to subsequent generations.

Contains fulltext : 292523.pdf (Publisher’s version ) (Closed access) Cladophialophora exuberans is a filamentous fungus related to black yeasts in the order Chaetothyriales. These melanized fungi are known for their 'dual ecology', often occurring in toxic environments and also being frequently involved in human infection. Particularly Cladophialophora exuberans, C. immunda, C. psammophila, and Exophiala mesophila have been described with a pronounced ability to degrade aromatic compounds and xenobiotic volatiles, such as benzene, toluene, ethyl-benzene, and xylene, and are candidates for bioremediation applications. The objective of the present study is the sequencing, assembly, and description of the whole genome of C. exuberans focusing on genes and pathways related to carbon and toxin management, assessing the tolerance and bioremediation of lead and copper, and verifying the presence of genes for metal homeostasis. Genomic evaluations were carried out through a comparison with sibling species including clinical and environmental strains. Tolerance of metals was evaluated via a microdilution method establishing minimum inhibitory (MIC) and fungicidal concentrations (MFC), and agar diffusion assays. Heavy metal bioremediation was evaluated via graphite furnace atomic absorption spectroscopy (GFAAS). The final assembly of C. exuberans comprised 661 contigs, with genome size of 38.10 Mb, coverage of 89.9X and a GC content of 50.8%. In addition, inhibition of growth was shown at concentrations of 1250 ppm for copper and at 625 ppm for lead, using the MIC method. In the agar tests, the strain grew at 2500 ppm of copper and lead. In GFAAS tests, uptake capacities were observed of 89.2% and 95.7% for copper and lead, respectively, after 21 experimental days. This study enabled the annotation of genes involved in heavy metal homeostasis and also contributed to a better understanding of the mechanisms used in tolerance of and adaptation to extreme conditions.

SARS-CoV-2 environmental monitoring can track the rate of viral contamination and can be used to establish preventive measures. This study aimed to detect by RT-PCR the presence of SARS-CoV-2 from inert surface samples in public health settings with a literature review about surface contamination and its burden on spread virus. Samples were collected from health settings in Curitiba, Brazil, between July and December 2020. A literature review was conducted using PRISMA. A total of 711 environmental surface samples were collected from outpatient areas, dental units, doctors’ offices, COVID-19 evaluation areas, and hospital units, of which 35 (4.9%) were positive for SARS-CoV-2 RNA. The frequency of environmental contamination was higher in primary care units than in hospital settings. The virus was detected on doctors’ personal items. Remarkably, the previously disinfected dental chair samples tested positive. These findings agree with those of other studies in which SARS-CoV-2 was found on inanimate surfaces. Detection of SARS-CoV-2 RNA on surfaces in public health settings, including those not meant to treat COVID-19, indicates widespread environmental contamination. Therefore, the intensification of disinfection measures for external hospital areas may be important for controlling community COVID-19 dissemination.

The fungal genus Fonsecaea contains etiological agents of human chromoblastomycosis, a (sub)tropical, (sub)cutaneous implantation disease caused by plant contact. The invasive potential differs significantly between species. Infections by Fonsecaea monophora are believed to originate from the environment and the species has been reported as one of the main causative agents of the disease, but also of cases of primary brain infection. The epidemiology of the disease has not been fully elucidated and questions related to its infection route and virulence are still to be clarified. The environmental species Fonsecaea erecta was isolated from organic material and living plants in endemic areas for chromoblastomycosis in Brazil. The present paper describes Agrobacteriumtumefaciens-mediated transformation (AMT) of the environmental species F. erecta and the pathogenic species F. monophora. We propose the use of Agrobacterium transformation for future gene function studies related to Fonsecaea virulence and pathogenicity. We evaluated the co-cultivation ratios 1:1, 10:1 and 100:1 (Agrobacterium:conidia) at 28 °C during 72 h. pAD1625 and pCAMDsRed plasmids were inserted into both species. Confirmation of transformation was realized by hph gene amplification and Southern blot determined the amount of foreign DNA integrated into the genome. In order to evaluate a potential link between environmental and clinical strains, we obtained red fluorescent transformants after pCAMDsRed insertion. We observed by confocal fluorescence microscopy that both F. monophora and F. erecta were able to colonize the palm Bactris gasipaes, penetrating the epidermis. These results contribute to understanding the ability of Fonsecaea species to adapt to different environmental and host conditions.

Made available in DSpace on 2016-09-23T15:23:44Z (GMT). No. of bitstreams: 1 R_F_S-111-2011_recurso.pdf: 467098 bytes, checksum: ac72c93a829f221072dc06db19cd0611 (MD5) Previous issue date: 2012-07-31 CNPQ Atualmente um grande número de animais de estimação silvestres tem inundado a sociedade moderna. Muitos destes animais são de outros países e podem causar um desequilíbrio ambiental quando soltos em solo brasileiro. Um dos animais silvestres mais procurados são as aranhas caranguejeiras devido o pequeno espaço que ocupam e pouco conhecimento técnico na sua manutenção. A caranguejeira Avicularia avicularia é uma aranha amazônica, dócil e de fácil manipulação, no entanto, pouco se sabe sobre os riscos microbiológicos que estas aranhas representam de fato. Este projeto tem o objetivo de determinar a microbiota presente nesta espécie de aranha e desta maneira, determinar se este animal alberga microrganismos patogênicos ao homem.