scholarly journals Interacting with Hemoglobin: Paracoccidioides spp. Recruits hsp30 on Its Cell Surface for Enhanced Ability to Use This Iron Source

2021 ◽  
Vol 7 (1) ◽  
pp. 21
Author(s):  
Aparecido Ferreira de Souza ◽  
Mariana Vieira Tomazett ◽  
Kleber Santiago Freitas e Silva ◽  
Juliana Santana de Curcio ◽  
Christie Ataides Pereira ◽  
...  
Keyword(s):  
Cell Wall ◽  
Protein Expression ◽  
Paracoccidioides Brasiliensis ◽  
Severe Illness ◽  
Primary Role ◽  
Dimorphic Fungi ◽  
Proteomic Data ◽  
Hemoglobin Binding ◽  
Paracoccidioides Spp ◽  
Essential Nutrient

Paracoccidioides spp. are thermally dimorphic fungi that cause paracoccidioidomycosis and can affect both immunocompetent and immunocompromised individuals. The infection can lead to moderate or severe illness and death. Paracoccidioides spp. undergo micronutrients deprivation within the host, including iron. To overcome such cellular stress, this genus of fungi responds in multiple ways, such as the utilization of hemoglobin. A glycosylphosphatidylinositol (GPI)-anchored fungal receptor, Rbt5, has the primary role of acquiring the essential nutrient iron from hemoglobin. Conversely, it is not clear if additional proteins participate in the process of using hemoglobin by the fungus. Therefore, in order to investigate changes in the proteomic level of P. lutzii cell wall, we deprived the fungus of iron and then treated those cells with hemoglobin. Deprived iron cells were used as control. Next, we performed cell wall fractionation and the obtained proteins were submitted to nanoUPLC-MSE. Protein expression levels of the cell wall F1 fraction of cells exposed to hemoglobin were compared with the protein expression of the cell wall F1 fraction of iron-deprived cells. Our results showed that P. lutzii exposure to hemoglobin increased the level of adhesins expression by the fungus, according to the proteomic data. We confirmed that the exposure of the fungus to hemoglobin increased its ability to adhere to macrophages by flow cytometry. In addition, we found that HSP30 of P. lutzii is a novel hemoglobin-binding protein and a possible heme oxygenase. In order to investigate the importance of HSP30 in the Paracoccidioides genus, we developed a Paracoccidioides brasiliensis knockdown strain of HSP30 via Agrobacterium tumefaciens-mediated transformation and demonstrated that silencing this gene decreases the ability of P. brasiliensis to use hemoglobin as a nutrient source. Additional studies are needed to establish HSP30 as a virulence factor, which can support the development of new therapeutic and/or diagnostic approaches.

Paracoccin overexpression in Paracoccidioides brasiliensis enhances fungal virulence by remodeling chitin properties of the cell wall

2020 ◽  
Author(s):  
Relber Aguiar Gonçales ◽  
Rafael Ricci-Azevedo ◽  
Vanessa C S Vieira ◽  
Fabrício F Fernandes ◽  
Sandra M de O Thomaz ◽  
...  
Keyword(s):  
Cell Wall ◽  
Paracoccidioides Brasiliensis ◽  
Chitinase Activity ◽  
Growth Media ◽  
Lung Pathology ◽  
Dimorphic Fungi ◽  
Fungal Virulence ◽  
Paracoccidioides Spp ◽  
Cell Growth And Viability ◽  
Etiological Agents

Abstract Background The thermo-dimorphic fungi Paracoccidioides spp. are the etiological agents of paracoccidioidomycosis. Although poorly studied, paracoccin (PCN) from P. brasiliensis has been shown to harbor lectinic, enzymatic, and immunomodulatory properties that impact disease development. Methods Mutants of P. brasiliensis overexpressing PCN (ov-PCN) were constructed by Agrobacterium tumefaciens-mediated transformation. Ov-PCN strains were analyzed and inoculated intranasally or intravenously to mice. Fungal burden, lung pathology, and survival were monitored to evaluate virulence. Electron microscopy was used to evaluate the size of chito-oligomer particles released by ov-PCN or wild-type strains to growth media. Results ov-PCN strains revealed no differences in cell growth and viability, although PCN overexpression favored cell separation, chitin processing that results in the release of smaller chito-oligomer particles, and enhanced virulence. Our data show that PCN triggers a critical effect in the cell wall biogenesis through the chitinase activity resulting from overexpression of PCN. As such, PCN overexpression aggravates the disease caused by P. brasiliensis. Conclusions Our data is consistent with a model in which PCN modulates the cell wall architecture via its chitinase activity. These findings highlight the potential for exploiting PCN function in future therapeutic approaches.

In silico identification of glycosylphosphatidylinositol-anchored proteins in Paracoccidioides spp.

2021 ◽  
Author(s):  
Relber A Gonçales ◽  
Ayda LM Salamanca ◽  
Luiz RB Júnior ◽  
Kleber SF e Silva ◽  
Elton JR de Vasconcelos ◽  
...  
Keyword(s):  
Cell Wall ◽  
In Silico ◽  
Paracoccidioides Brasiliensis ◽  
In Silico Analysis ◽  
Diagnostic Tools ◽  
Future Research ◽  
Immunological Tests ◽  
Paracoccidioides Spp ◽  
In Silico Identification ◽  
In Silico Analyses

Aim: To predict glycosylphosphatidylinositol (GPI)-anchored proteins in the genome of Paracoccidioides brasiliensis and Paracoccidioides lutzii. Materials & methods: Five different bioinformatics tools were used for predicting GPI-anchored proteins; we considered as GPI-anchored proteins those detected by at least two in silico analysis methods. We also performed the proteomic analysis of P. brasiliensis cell wall by mass spectrometry. Results: Hundred GPI-anchored proteins were predicted in P. brasiliensis and P. lutzii genomes. A series of 57 proteins were classified in functional categories and 43 conserved proteins were reported with unknown functions. Four proteins identified by in silico analyses were also identified in the cell wall proteome. Conclusion: The data obtained in this study are important resources for future research of GPI-anchored proteins in Paracoccidioides spp. to identify targets for new diagnostic tools, drugs and immunological tests.

scholarly journals In silico identification of GPI-anchored proteins in Paracoccidioides

2018 ◽  
Author(s):  
L.R. Basso ◽  
R.A. Gonçales ◽  
E.J.R Vasconcelos ◽  
T.F. Reis ◽  
P. C. Ruy ◽  
...  
Keyword(s):  
Cell Wall ◽  
In Silico ◽  
Glycoside Hydrolases ◽  
Cellular Mechanisms ◽  
Dimorphic Fungi ◽  
A Genome ◽  
Paracoccidioides Spp ◽  
Gpi Proteins ◽  
Eukaryotic Organisms ◽  
Prediction Approach

ABSTRACTGlycosylphosphatidylinositol-anchored proteins (GPI-proteins) are widely found in eukaryotic organisms. In fungi, GPI-proteins are thought to be involved in diverse cellular mechanisms such as cell wall biosynthesis and cell wall remodeling, adhesion, antigenicity, and virulence. The conserved structural domains of GPI-protein allow the utilization ofin silicoprediction approach to identify this class of proteins using a genome-wide analysis. We used different previously characterized algorithms to search for genes that encode predicted GPI-proteins in the genome ofP. brasiliensis and P. lutzii, thermal dimorphic fungi that causes paracoccidioidomycosis (PCM). By using these methods, 98 GPI-proteins were found inP. brasiliensiswith orthologs inP. lutzii. A series of 28 GPI-proteins were classified in functional categories (such as glycoside hydrolases, chitin-processing proteins, and proteins involved in the biogenesis of the cell wall). Furthermore, 70 GPI-proteins exhibited homology with hypothetical conserved proteins of unknown function. These data will be an important resource for the future analysis of GPI-proteins inParacoccidioides spp.

1,3-β-d-Glucan synthase of Paracoccidioides brasiliensis: recombinant protein, expression and cytolocalization in the yeast and mycelium phases

2010 ◽  
Vol 114 (10) ◽  
pp. 809-816 ◽  
Author(s):  
Patrícia Kott Tomazett ◽  
Carlos Roberto Félix ◽  
Henrique Leonel Lenzi ◽  
Fabrícia de Paula Faria ◽  
Célia Maria de Almeida Soares ◽  
...  
Keyword(s):  
Recombinant Protein ◽  
Protein Expression ◽  
Recombinant Protein Expression ◽  
Paracoccidioides Brasiliensis ◽  
Glucan Synthase

scholarly journals Cell Wall Glucans of the Yeast and Mycelial Forms of Paracoccidioides brasiliensis

1970 ◽  
Vol 101 (3) ◽  
pp. 675-680 ◽  
Author(s):  
Fuminori Kanetsuna ◽  
Luis M. Carbonell
Keyword(s):  
Cell Wall ◽  
Paracoccidioides Brasiliensis

scholarly journals The Role of Dimorphism Regulating Histidine Kinase (Drk1) in the Pathogenic Fungus Paracoccidioides brasiliensis Cell Wall

2021 ◽  
Vol 7 (12) ◽  
pp. 1014
Author(s):  
Marina Valente Navarro ◽  
Yasmin Nascimento de Barros ◽  
Wilson Dias Segura ◽  
Alison Felipe Alencar Chaves ◽  
Grasielle Pereira Jannuzzi ◽  
...  
Keyword(s):  
Cell Wall ◽  
Histidine Kinase ◽  
Mammalian Cells ◽  
Paracoccidioides Brasiliensis ◽  
Pathogenic Fungus ◽  
Fungal Resistance ◽  
Phagocytic Index ◽  
Mammalian Host ◽  
Control Group

Dimorphic fungi of the Paracoccidioides genus are the causative agents of paracoccidioidomycosis (PCM), an endemic disease in Latin America with a high incidence in Brazil. This pathogen presents as infective mycelium at 25 °C in the soil, reverting to its pathogenic form when inhaled by the mammalian host (37 °C). Among these dimorphic fungal species, dimorphism regulating histidine kinase (Drk1) plays an essential role in the morphological transition. These kinases are present in bacteria and fungi but absent in mammalian cells and are important virulence and cellular survival regulators. Hence, the purpose of this study was to investigate the role of PbDrk1 in the cell wall modulation of P. brasiliensis. We observed that PbDrk1 participates in fungal resistance to different cell wall-disturbing agents by reducing viability after treatment with iDrk1. To verify the role of PbDRK1 in cell wall morphogenesis, qPCR results showed that samples previously exposed to iDrk1 presented higher expression levels of several genes related to cell wall modulation. One of them was FKS1, a β-glucan synthase that showed a 3.6-fold increase. Furthermore, confocal microscopy analysis and flow cytometry showed higher β-glucan exposure on the cell surface of P. brasiliensis after incubation with iDrk1. Accordingly, through phagocytosis assays, a significantly higher phagocytic index was observed in yeasts treated with iDrk1 than the control group, demonstrating the role of PbDrk1 in cell wall modulation, which then becomes a relevant target to be investigated. In parallel, the immune response profile showed increased levels of proinflammatory cytokines. Finally, our data strongly suggest that PbDrk1 modulates cell wall component expression, among which we can identify β-glucan. Understanding this signalling pathway may be of great value for identifying targets of antifungal molecular activity since HKs are not present in mammals.

scholarly journals Molecular Tools for Detection and Identification of Paracoccidioides Species: Current Status and Future Perspectives

2020 ◽  
Vol 6 (4) ◽  
pp. 293 ◽  
Author(s):  
Breno Gonçalves Pinheiro ◽  
Rosane Christine Hahn ◽  
Zoilo Pires de Camargo ◽  
Anderson Messias Rodrigues
Keyword(s):  
Current Status ◽  
Large Area ◽  
Mycelial Form ◽  
Dimorphic Fungi ◽  
Laboratory Techniques ◽  
Detection And Identification ◽  
Paracoccidioides Spp ◽  
Taxonomic Changes ◽  
Immunological Assays ◽  
Mycotic Disease

Paracoccidioidomycosis (PCM) is a mycotic disease caused by the Paracoccidioides species, a group of thermally dimorphic fungi that grow in mycelial form at 25 °C and as budding yeasts when cultured at 37 °C or when parasitizing the host tissues. PCM occurs in a large area of Latin America, and the most critical regions of endemicity are in Brazil, Colombia, and Venezuela. The clinical diagnosis of PCM needs to be confirmed through laboratory tests. Although classical laboratory techniques provide valuable information due to the presence of pathognomonic forms of Paracoccidioides spp., nucleic acid-based diagnostics gradually are replacing or complementing culture-based, biochemical, and immunological assays in routine microbiology laboratory practice. Recently, taxonomic changes driven by whole-genomic sequencing of Paracoccidioides have highlighted the need to recognize species boundaries, which could better ascertain Paracoccidioides taxonomy. In this scenario, classical laboratory techniques do not have significant discriminatory power over cryptic agents. On the other hand, several PCR-based methods can detect polymorphisms in Paracoccidioides DNA and thus support species identification. This review is focused on the recent achievements in molecular diagnostics of paracoccidioidomycosis, including the main advantages and pitfalls related to each technique. We discuss these breakthroughs in light of taxonomic changes in the Paracoccidioides genus.

scholarly journals From element to development: the power of the essential micronutrient boron to shape morphological processes in plants

2020 ◽  
Vol 71 (5) ◽  
pp. 1681-1693 ◽  
Author(s):  
Michaela S Matthes ◽  
Janlo M Robil ◽  
Paula McSteen
Keyword(s):  
Cell Wall ◽  
Current Understanding ◽  
Micronutrient Deficiencies ◽  
Developmental Defects ◽  
Essential Nutrient ◽  
Experimental Approaches ◽  
Morphological Processes ◽  
Underlying Mechanisms ◽  
Mutant Phenotypes

Abstract Deficiency of the essential nutrient boron (B) in the soil is one of the most widespread micronutrient deficiencies worldwide, leading to developmental defects in root and shoot tissues of plants, and severe yield reductions in many crops. Despite this agricultural importance, the underlying mechanisms of how B shapes plant developmental and morphological processes are still not unequivocally understood in detail. This review evaluates experimental approaches that address our current understanding of how B influences plant morphological processes by focusing on developmental defects observed under B deficiency. We assess what is known about mechanisms that control B homeostasis and specifically highlight: (i) limitations in the methodology that is used to induce B deficiency; (ii) differences between mutant phenotypes and normal plants grown under B deficiency; and (iii) recent research on analyzing interactions between B and phytohormones. Our analysis highlights the need for standardized methodology to evaluate the roles of B in the cell wall versus other parts of the cell.

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