Extracellular Vesicle-Associated Transitory Cell Wall Components and Their Impact on the Interaction of Fungi with Host Cells

Submitted by Fabricia Pimenta ([email protected]) on 2018-06-29T18:34:23Z No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2016.pdf: 690221 bytes, checksum: a96164d483123b78f71bffabda9ffa1b (MD5)Approved for entry into archive by Fabricia Pimenta ([email protected]) on 2019-01-11T18:29:02Z (GMT) No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2016.pdf: 690221 bytes, checksum: a96164d483123b78f71bffabda9ffa1b (MD5)Made available in DSpace on 2019-01-11T18:29:02Z (GMT). No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2016.pdf: 690221 bytes, checksum: a96164d483123b78f71bffabda9ffa1b (MD5) Previous issue date: 2016-07-08Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Professor Paulo de Góes. Laboratório de Glicobiologia de Eucariotos. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Professor Paulo de Góes. Laboratório de Glicobiologia de Eucariotos. Rio de Janeiro, RJ, Brazil.Stony Brook University. Department of Molecular Genetics and Microbiology. Stony Brook, NY, USA / Veterans Administration Medical Center. Northport, NY, USA.Albert Einstein College of Medicine. Department of Microbiology and Immunology and Medicine. Bronx, NY, USA.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Professor Paulo de Góes. Laboratório de Glicobiologia de Eucariotos. Rio de Janeiro, RJ, Brazil.Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Professor Paulo de Góes. Laboratório de Glicobiologia de Eucariotos. Rio de Janeiro, RJ, Brazil.Fundação Oswaldo Cruz. Centro de Desenvolvimento Tecnológico em Saúde. Rio de Janeiro, RJ, Brazil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Professor Paulo de Góes. Laboratório de Glicobiologia de Eucariotos. Rio de Janeiro, RJ, Brazil.Classic cell wall components of fungi comprise the polysaccharides glucans and chitin, in association with glycoproteins and pigments. During the last decade, however, system biology approaches clearly demonstrated that the composition of fungal cell walls include atypical molecules historically associated with intracellular or membrane locations. Elucidation of mechanisms by which many fungal molecules are exported to the extracellular space suggested that these atypical components are transitorily located to the cell wall. The presence of extracellular vesicles (EVs) at the fungal cell wall and in culture supernatants of distinct pathogenic species suggested a highly functional mechanism of molecular export in these organisms. Thus, the passage of EVs through fungal cell walls suggests remarkable molecular diversity and, consequently, a potentially variable influence on the host antifungal response. On the basis of information derived from the proteomic characterization of fungal EVs from the yeasts Cryptoccocus neoformans and Candida albicans and the dimorphic fungi Histoplasma capsulatum and Paracoccidioides brasiliensis, our manuscript is focused on the clear view that the fungal cell wall is much more complex than previously thought

Extracellular vesicle-mediated export of fungal RNA

Extracellular vesicles (EVs) play an important role in the biology of various organisms, including fungi, in which they are required for the trafficking of molecules across the cell wall. Fungal EVs contain a complex combination of macromolecules, including proteins, lipids and glycans. in this work, we aimed to describe and characterize RNA in EV preparations from the human pathogens Cryptococcus neoformans, Paracoccidiodes brasiliensis and Candida albicans, and from the model yeast Saccharomyces cerevisiae. the EV RNA content consisted mostly of molecules less than 250 nt long and the reads obtained aligned with intergenic and intronic regions or specific positions within the mRNA. We identified 114 ncRNAs, among them, six small nucleolar (snoRNA), two small nuclear (snRNA), two ribosomal (rRNA) and one transfer (tRNA) common to all the species considered, together with 20 sequences with features consistent with miRNAs. We also observed some copurified mRNAs, as suggested by reads covering entire transcripts, including those involved in vesicle-mediated transport and metabolic pathways. We characterized for the first time RNA molecules present in EVs produced by fungi. Our results suggest that RNA-containing vesicles may be determinant for various biological processes, including cell communication and pathogenesis.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)Instituto Nacional de Ciencia e Tecnologia de Inovacao em Doencas Negligenciadas (INCT-IDN)Brazilian agency Fundacao Araucaria - PRONEXBrazilian agency Papes-FiocruzUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilFundacao Oswaldo Cruz, CDTS, Rio de Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, Inst Microbiol Prof Paulo de Goes, BR-21941 Rio de Janeiro, RJ, BrazilFiocruz PR, Fundacao Oswaldo Cruz, Inst Carlos Chagas, Curitiba, PR, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Dept Microbiol Imunol & Parasitol, São Paulo, BrazilWeb of Scienc

Genes essenciais de cryptococcus

Fundação Oswaldo CruzCiências BiológicasDepositad

Perceptions of consent, permission structures and approaches to the community: a rapid ethical assessment performed in North West Cameroon

BACKGROUND Understanding local contextual factors is important when conducting international collaborative studies in low-income country settings. Rapid ethical assessment (a brief qualitative intervention designed to map the ethical terrain of a research setting prior to recruitment of participants), has been used in a range of research-naïve settings. We used rapid ethical assessment to explore ethical issues and challenges associated with approaching communities and gaining informed consent in North West Cameroon. METHODS This qualitative study was carried out in two health districts in the North West Region of Cameroon between February and April 2012. Eleven focus group discussions (with a total of 107 participants) were carried out among adult community members, while 72 in-depth interviews included health workers, non-government organisation staff and local community leaders. Data were collected in English and pidgin, translated where necessary into English, transcribed and coded following themes. RESULTS Many community members had some understanding of informed consent, probably through exposure to agricultural research in the past. Participants described a centralised permission-giving structure in their communities, though there was evidence of some subversion of these structures by the educated young and by women. Several acceptable routes for approaching the communities were outlined, all including the health centre and the Fon (traditional leader). The importance of time spent in sensitizing the community and explaining information was stressed. CONCLUSIONS Respondents held relatively sophisticated understanding of consent and were able to outline the structures of permission-giving in the community. Although the structures are unique to these communities, the role of certain trusted groups is common to several other communities in Kenya and Ethiopia explored using similar techniques. The information gained through Rapid Ethical Assessment will form an important guide for future studies in North West Cameroon

Characterization of Yeast Extracellular Vesicles: Evidence for the Participation of Different Pathways of Cellular Traffic in Vesicle Biogenesis

Background: Extracellular vesicles in yeast cells are involved in the molecular traffic across the cell wall. In yeast pathogens, these vesicles have been implicated in the transport of proteins, lipids, polysaccharide and pigments to the extracellular space. Cellular pathways required for the biogenesis of yeast extracellular vesicles are largely unknown. Methodology/Principal Findings: We characterized extracellular vesicle production in wild type (WT) and mutant strains of the model yeast Saccharomyces cerevisiae using transmission electron microscopy in combination with light scattering analysis, lipid extraction and proteomics. WT cells and mutants with defective expression of Sec4p, a secretory vesicleassociated Rab GTPase essential for Golgi-derived exocytosis, or Snf7p, which is involved in multivesicular body (MVB) formation, were analyzed in parallel. Bilayered vesicles with diameters at the 100–300 nm range were found in extracellular fractions from yeast cultures. Proteomic analysis of vesicular fractions from the cells aforementioned and additional mutants with defects in conventional secretion pathways (sec1-1, fusion of Golgi-derived exocytic vesicles with the plasm

Potential Roles of Fungal Extracellular Vesicles during Infection

Submitted by Fabricia Pimenta ([email protected]) on 2018-06-29T19:43:36Z No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2016a.pdf: 1107301 bytes, checksum: ff6553fccea25073308ca3455a19b55e (MD5)Approved for entry into archive by Fabricia Pimenta ([email protected]) on 2018-07-26T17:25:44Z (GMT) No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2016a.pdf: 1107301 bytes, checksum: ff6553fccea25073308ca3455a19b55e (MD5)Made available in DSpace on 2018-07-26T17:25:45Z (GMT). No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2016a.pdf: 1107301 bytes, checksum: ff6553fccea25073308ca3455a19b55e (MD5) Previous issue date: 2016-06-29Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Góes. Departamento de Microbiologia Geral. Rio de Janeiro, RJ, Brasil / University Stony Brook. Department of Molecular Genetics and Microbiology. Stony Brook, New York, USA.University Stony Brook. Department of Molecular Genetics and Microbiology. Stony Brook, New York, USA.Fundação Oswaldo Cruz. Centro de Desenvolvimento Tecnológico em Saúde. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Góes. Rio de Janeiro, RJ, Brasil.University, Stony Brook. Department of Molecular Genetics and Microbiology. Stony Brook, New York, USA / Veterans Administration Medical Center. Northport, NY, USA.Extracellular vesicles (EVs) are produced by virtually all cell types. Within the past few years, work in this field has revealed more information about fungal EVs. Fungal EVs have been shown to carry proteins, lipids, pigments, polysaccharides, and RNA; these components are known virulence factors, a fact which supports the hypothesis that fungal EVs concentrate pathogenic determinants. Additionally, recent studies have demonstrated that fungal EVs stimulate the host immune system. In this review, putative roles of fungal EVs are discussed, including their potential as vaccination tools and their possible contribution to pathogenesis in invasive fungal diseases

Sleep in thyrotoxicosis

Objective: Pattern of sleep in hyperthyroid state / thyrotoxicosis has not been systematically studied. It is being characterized as poor without further elaboration. We analyzed the pattern of sleep in a large sample of individuals with thyrotoxicosis who came to our endocrine center in southern India. Materials and Methods: We identified individuals with the diagnosis of ′thyrotoxicosis′ from our electronic medical record database, and evaluated clinical parameters and pattern of their sleep: difficulty in falling asleep (DFA), difficulty in maintaining sleep (DMS), excess daytime sleepiness). In the first phase, univariate analysis with logistic regression was performed. Multivariate logistic regression was performed in the next phase on variables with a P-value < 0.1: these were considered as potential categories/ variables. Results: In model response variable with DFA, multivariate logistic regression predicted that subjects with abnormal appetite (more 1.7 or less 2.2), change in bowel motion (loose 1.5 or constipation 2.8), in mood (easy loss of temper 3.4), change of voice -- hoarse 7.4 or moderately hoarse 3.1), tended to have higher chances of difficulty in falling asleep (DFA). Patients with tremor (yes = 5.4) had greater likelihood of difficulty in maintaining sleep (DMS). Conclusions: Individuals with hyperthyroidism/thyrotoxicosis principally had difficulty in falling asleep DFA, which was related to hyperkinetic features

Where Do They Come from and Where Do They Go : Candidates for Regulating Extracellular Vesicle Formation in Fungi

In the past few years, extracellular vesicles (EVs) from at least eight fungal species were characterized. EV proteome in four fungal species indicated putative biogenesis pathways and suggested interesting similarities with mammalian exosomes. Moreover, as observed for mammalian exosomes, fungal EVs were demonstrated to be immunologically active. Here we review the seminal and most recent findings related to the production of EVs by fungi. Based on the current literature about secretion of fungal molecules and biogenesis of EVs in eukaryotes, we focus our discussion on a list of cellular proteins with the potential to regulate vesicle biogenesis in the fungi.Science, Faculty ofNon UBCMicrobiology and Immunology, Department ofReviewedFacult

Genes essenciais de cryptococcus

Fundação Oswaldo CruzCiências BiológicasDepositad

The Anti-helminthic Compound Mebendazole Has Multiple Antifungal Effects against Cryptococcus neoformans

Submitted by Fabricia Pimenta ([email protected]) on 2018-06-29T19:03:08Z No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2017a.pdf: 3873194 bytes, checksum: 99621cb2d1cf68a20e492eae8b6b1757 (MD5)Approved for entry into archive by Fabricia Pimenta ([email protected]) on 2018-07-26T16:28:40Z (GMT) No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2017a.pdf: 3873194 bytes, checksum: 99621cb2d1cf68a20e492eae8b6b1757 (MD5)Made available in DSpace on 2018-07-26T16:28:40Z (GMT). No. of bitstreams: 1 ve_Marcio_Rodrigues_etal_CDTS_2017a.pdf: 3873194 bytes, checksum: 99621cb2d1cf68a20e492eae8b6b1757 (MD5) Previous issue date: 2017-03-28Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Góes. Laboratório de Biologia Celular de Leveduras Patogênicas Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio Grande do Sul. Centro de Biotecnologia. Porto Alegre, RS, Brasil.Universidade Federal do Rio Grande do Sul. Centro de Biotecnologia. Porto Alegre, RS, Brasil.Fundação Oswaldo Cruz. Centro de Desenvolvimento Tecnológico em Saúde. Rio de Janeiro, RJ, Brasil.Universidade Federal do Rio Grande do Sul. Centro de Biotecnologia. Departamento de Biologia Molecular e Biotecnologia. Porto Alegre, RS, Brasil.Universidade Federal do Rio Grande do Sul. Centro de Biotecnologia. Departamento de Biologia Molecular e Biotecnologia. Porto Alegre, RS, Brasil.Universidade Federal do Rio Grande do Sul. Centro de Biotecnologia. Departamento de Biologia Molecular e Biotecnologia. Porto Alegre, RS, Brasil.Veterans Administration Medical Center. Northport, NY, USA / Stony Brook University. Department of Molecular Genetics and Microbiology. Stony Brook, NY, USA.Universidade Federal do Rio Grande do Sul. Centro de Biotecnologia. Departamento de Biologia Molecular e Biotecnologia. Porto Alegre, RS, Brasil.Fundação Oswaldo Cruz. Centro de Desenvolvimento Tecnológico em Saúde. Rio de Janeiro, RJ, Brasil / Universidade Federal do Rio de Janeiro. Instituto de Microbiologia Paulo de Góes. Laboratório de Biologia Celular de Leveduras Patogênicas Rio de Janeiro, RJ, Brasil.Cryptococcus neoformans is the most lethal pathogen of the central nervous system. The gold standard treatment of cryptococcosis, a combination of amphotericin B with 5-fluorocytosine, involves broad toxicity, high costs, low efficacy, and limited worldwide availability. Although the need for new antifungals is clear, drug research and development (R&D) is costly and time-consuming. Thus, drug repurposing is an alternative to R&D and to the currently available tools for treating fungal diseases. Here we screened a collection of compounds approved for use in humans seeking for those with anti-cryptococcal activity. We found that benzimidazoles consist of a broad class of chemicals inhibiting C. neoformans growth. Mebendazole and fenbendazole were the most efficient antifungals showing in vitro fungicidal activity. Since previous studies showed that mebendazole reaches the brain in biologically active concentrations, this compound was selected for further studies. Mebendazole showed antifungal activity against phagocytized C. neoformans, affected cryptococcal biofilms profoundly and caused marked morphological alterations in C. neoformans, including reduction of capsular dimensions. Amphotericin B and mebendazole had additive anti-cryptococcal effects. Mebendazole was also active against the C. neoformans sibling species, C. gattii. To further characterize the effects of the drug a random C. gattii mutant library was screened and indicated that the antifungal activity of mebendazole requires previously unknown cryptococcal targets. Our results indicate that mebendazole is as a promising prototype for the future development of anti-cryptococcal drugs