Interactions of the emerging fungus with reveal phenotypic changes with direct implications on the response to stress and virulence.

Unlabelled: is an emerging fungal pathogen notable for its resistance to multiple antifungals and ability to survive in various environments. Understanding the interactions between and environmental protozoa, such as could provide insights into fungal adaptability and pathogenicity. Two isolates (MMC1 and MMC2) were co-cultured with to examine interaction dynamics, survival, stress responses, growth, virulence, biofilm formation, and antifungal susceptibility.

Saps1-3 Antigens in : Differential Modulation Following Exposure to Soluble Proteins, Mammalian Cells, and Infection in Mice.

The secreted aspartic peptidases (Saps) of play crucial roles in various steps of fungal-host interactions. Using a flow cytometry approach, this study investigated the expression of Saps1-3 antigens after (i) incubation with soluble proteins, (ii) interaction with mammalian cells, and (iii) infection in immunosuppressed BALB/c mice. Supplementation strategies involving increasing concentrations of bovine serum albumin (BSA) added to yeast carbon base (YCB) medium as the sole nitrogenous source revealed a positive and significant correlation between BSA concentration and both the growth rate and the percentage of fluorescent cells (%FC) labeled with anti-Saps1-3 antibodies.

Comprehensive characterization of extracellular vesicles produced by environmental (Neff) and clinical (T4) strains of .

We conducted a comprehensive comparative analysis of extracellular vesicles (EVs) from two strains, Neff (environmental) and T4 (clinical). Morphological analysis via transmission electron microscopy revealed slightly larger Neff EVs (average = 194.5 nm) compared to more polydisperse T4 EVs (average = 168.

Spatio-temporal six-year retrospective study on dermatophytosis in Rio de Janeiro, Southeast Brazil: A tropical tourist locality tale.

Trichophyton, Microsporum, Nannizzia and Epidermophyton genera cause dermatophytosis, the most common and highly contagious infectious skin disease. Rio de Janeiro is one of the most visited cities in the Southern Hemisphere, located in the most visited state of Brazil. This retrospective study investigated epidemiological and laboratorial aspects of dermatophytosis in Rio de Janeiro state, Brazil, by using spatiotemporal analysis.

Repositioning Lopinavir, an HIV Protease Inhibitor, as a Promising Antifungal Drug: Lessons Learned from -In Silico, In Vitro and In Vivo Approaches.

The repurposing strategy was applied herein to evaluate the effects of lopinavir, an aspartic protease inhibitor currently used in the treatment of HIV-infected individuals, on the globally widespread opportunistic human fungal pathogen by using in silico, in vitro and in vivo approaches in order to decipher its targets on fungal cells and its antifungal mechanisms of action. Secreted aspartic proteases (Saps) are the obviously main target of lopinavir. To confirm this hypothesis, molecular docking assays revealed that lopinavir bound to the Sap2 catalytic site of as well as inhibited the Sap hydrolytic activity in a typically dose-dependent manner.

Peptidogalactomannan from Histoplasma capsulatum yeast cell wall: role of the chemical structure in recognition and activation by peritoneal macrophages.

Histoplasma capsulatum is the causative agent of histoplasmosis, a systemic disease responsible for most reported causes of morbidity and mortality among immunosuppressed individuals. Peptidogalactomannan (pGM) was purified from the yeast cell wall of H. capsulatum isolated from bats, and its structure and involvement in modulating the host immune response were evaluated.

Promising application of the SsCBF ELISA test to monitor the therapeutic response of feline sporotrichosis caused by Sporothrix brasiliensis from Brazilian epidemics.

Sporotrichosis zoonotic transmission by cats has obtained hyperendemic magnitude in Rio de Janeiro, Brazil. Atypical cases, relapses, and reinfections as well as reduced diagnostic sensitivity of conventional methods have been reported. Previously, the anti-SsCBF enzyme-linked immunosorbent assay (ELISA) test was shown to be useful as a diagnostic tool for human sporotrichosis.

Polymorphism in the IL-1β promoter is associated with IgG antibody response to circumsporozoite protein repeats of Plasmodium vivax.

Background: It is well established that infection by Plasmodium vivax is a result of host-parasite interactions. In the present study, association with the IL1/IL2 cytokine profiles, anticircumsporozoite protein antibody levels and parasitic loads was evaluated in individuals naturally infected with P. vivax in an endemic area of the Brazilian Amazon.

Histoplasma capsulatum-induced extracellular DNA trap release in human neutrophils.

Neutrophils are leukocytes that are capable of eliminating both intra- and extracellular pathogens by mechanisms such as phagocytosis, degranulation, and release of neutrophil extracellular traps (NETs). Histoplasma capsulatum var. capsulatum (H.

Domestic feline contribution in the transmission of Sporothrix in Rio de Janeiro State, Brazil: a comparison between infected and non-infected populations.

Background: Sporotrichosis is a neglected zoonosis caused by pathogenic fungi belonging to the Sporothrix schenckii complex. In Rio de Janeiro state, this disease reached an epidemic status with over 4700 domestic felines and around 4000 humans affected since the mid-90s. The present study evaluated clinical and epidemiological aspects and also the frequency of colonization and infection by these fungi in healthy cats and among those with suspicious cutaneous lesions, inhabiting four Rio de Janeiro state distinct areas.

Peptidorhamnomannan negatively modulates the immune response in a scedosporiosis murine model.

In this study, we analyzed the impact of immunization with the peptidorhamnomannan (PRM) from the cell wall of the fungus Scedosporium (Lomentospora) prolificans in a murine model of invasive scedosporiosis. Immunization with PRM decreased the survival of mice infected with S. prolificans.

Antibodies Against Glycolipids Enhance Antifungal Activity of Macrophages and Reduce Fungal Burden After Infection with Paracoccidioides brasiliensis.

Paracoccidioidomycosis is a fungal disease endemic in Latin America. Polyclonal antibodies to acidic glycosphingolipids (GSLs) from Paracoccidioides brasiliensis opsonized yeast forms in vitro increasing phagocytosis and reduced the fungal burden of infected animals. Antibodies to GSL were active in both prophylactic and therapeutic protocols using a murine intratracheal infection model.

Candida haemulonii complex: species identification and antifungal susceptibility profiles of clinical isolates from Brazil.

Objectives: The emerging fungal pathogens comprising the Candida haemulonii complex (Candida haemulonii, Candida haemulonii var. vulnera and Candida duobushaemulonii) are notable for their antifungal resistance. Twelve isolates with phenotypic similarity to C.

Protease and phospholipase activities of Candida spp. isolated from cutaneous candidiasis.

Background: Cases of superficial and invasive mycoses caused by emerging species of Candida have been increasingly reported over the last thirty years. The production of hydrolytic enzymes plays a central role in the fungal infective process. In Candida infections the secretion of both proteases and phospholipases are well-known virulence attributes.

Peptides of the constant region of antibodies display fungicidal activity.

Synthetic peptides with sequences identical to fragments of the constant region of different classes (IgG, IgM, IgA) of antibodies (Fc-peptides) exerted a fungicidal activity in vitro against pathogenic yeasts, such as Candida albicans, Candida glabrata, Cryptococcus neoformans, and Malassezia furfur, including caspofungin and triazole resistant strains. Alanine-substituted derivatives of fungicidal Fc-peptides, tested to evaluate the critical role of each residue, displayed unaltered, increased or decreased candidacidal activity in vitro. An Fc-peptide, included in all human IgGs, displayed a therapeutic effect against experimental mucosal and systemic candidiasis in mouse models.

Metallopeptidase inhibitors arrest vital biological processes in the fungal pathogen Scedosporium apiospermum.

Scedosporium apiospermum is an emerging agent of opportunistic mycoses in humans. Previously, we showed that mycelia of S. apiospermum secreted metallopeptidases which were directly linked to the destruction of key host proteins.

Biochemical characterization of potential virulence markers in the human fungal pathogen Pseudallescheria boydii.

The ubiquitous Pseudallescheria boydii (anamorph Scedosporium apiospermum) is a saprophytic filamentous fungus recognized as a potent etiologic agent of a wide variety of infections in immunocompromised as well as in immunocompetent patients. Very little is known about the virulence factors expressed by this fungal pathogen. The present review provides an overview of recent discoveries related to the identification and biochemical characterization of potential virulence attributes produced by P.

Proteins and peptidases from conidia and mycelia of Scedosporium apiospermum strain HLPB.

The conidia-mycelia transformation is an essential step during the life cycle of the fungal human pathogens of the Pseudallescheria boydii complex. In the present study, we have analyzed the protein and peptidase profiles in two distinct morphological stages, conidia and mycelia, of Scedosporium apiospermum sensu stricto. Proteins synthesized by the mycelia, migrating at the ranges of 62-48 and 22-18 kDa, were not detected from the conidial extract.

Mycelial forms of Pseudallescheria boydii present ectophosphatase activities.

Phosphatase activities were characterized in intact mycelial forms of Pseudallescheria boydii, which are able to hydrolyze the artificial substrate p-nitrophenylphosphate (p-NPP) to p-nitrophenol (p-NP) at a rate of 41.41+/-2.33 nmol p-NP per h per mg dry weight, linearly with increasing time and with increasing cell density.

Extracellular peptidase in the fungal pathogen Pseudallescheria boydii.

Pseudallescheria boydii is a ubiquitous filamentous fungus capable of causing invasive disease in humans. In the present study, using sodium dodecyl sulfate-polyacrylamide gels containing bovine serum albumin as co-polymerized substrate, we identified a 28-kDa proteolytic activity released to the extracellular environment by mycelia of P. boydii.

Pseudallescheria boydii releases metallopeptidases capable of cleaving several proteinaceous compounds.

Pseudallescheria boydii is an opportunistic filamentous fungus that causes serious infections in humans. Virulence attributes expressed by P. boydii are unknown.

Structures of the O-linked oligosaccharides of a complex glycoconjugate from Pseudallescheria boydii.

Nonreducing O-linked oligosaccharides were obtained from the peptidorhamnomannan of mycelia of Pseudallescheria boydii by alkaline beta-elimination under reducing conditions. They were separated by gel filtration chromatography to give three oligosaccharide fractions. The major oligosaccharide from fraction 1 was characterized by a combination of techniques including electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI MS/MS), matrix-assisted laser desorption ionization mass spectrometry (MALDI MS), nuclear magnetic resonance (NMR), and methylation gas-liquid chromatography-mass spectrometry (GC-MS) analysis.

Involvement of peptidorhamnomannan in the interaction of Pseudallescheria boydii and HEp2 cells.

Pseudallescheria boydii is an emerging fungal pathogen that has a worldwide distribution. Virulence mechanisms of P. boydii are largely unknown.

Structure and biological functions of fungal cerebrosides.

Ceramide monohexosides (CMHs, cerebrosides) are glycosphingolipids composed of a hydrophobic ceramide linked to one sugar unit. In fungal cells, CMHs are very conserved molecules consisting of a ceramide moiety containing 9-methyl-4,8-sphingadienine in amidic linkage to 2-hydroxyoctadecanoic or 2-hydroxyhexadecanoic acids, and a carbohydrate portion consisting of one residue of glucose or galactose. 9-Methyl 4,8-sphingadienine-containing ceramides are usually glycosylated to form fungal cerebrosides, but the recent description of a ceramide dihexoside (CDH) presenting phytosphingosine in Magnaporthe grisea suggests the existence of alternative pathways of ceramide glycosylation in fungal cells.

Glucosylceramides in Colletotrichum gloeosporioides are involved in the differentiation of conidia into mycelial cells.

Glucosylceramides (GlcCer) were extracted from the plant pathogen Colletotrichum gloeosporioides and purified by several chromatographic steps. By using electrospray ionization mass spectrometry and nuclear magnetic resonance, GlcCer from C. gloeosporioides were identified as N-2'-hydroxyoctadecanoyl-1-beta-D-glucopyranosyl-9-methyl-4,8-sphingadienine and N-2'-hydroxyoctadecenoyl-1-beta-D-glucopyranosyl-9-methyl-4,8-sphingadienine.