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Sporothrix brasiliensis is the main agent of zoonotic sporotrichosis transmitted by domestic cats in South America. In humans, sporotrichosis commonly presents with cutaneous or lymphocutaneous lesions, and in cats, with multiple ulcerated skin lesions associated with enlarged lymph nodes and respiratory signs. Fungal virulence factors may affect the clinical presentation of the mycoses. Sporothrix spp. present some virulence factors. This study aims to compare 24 S. brasiliensis strains from 12 familiar outbreaks of cat-to-human transmitted sporotrichosis. Fungal growth in different substrates, thermotolerance, resistance to oxidative stress, and production of enzymes were evaluated. An invertebrate model of experimental infection was used to compare the virulence of the strains. The strains grew well on glucose and N-acetyl-D-glucosamine but poorly on lactate. Their thermotolerance was moderate to high. All strains were susceptible to hydrogen peroxide, and the majority produced hemolysins but not phospholipase and esterase. There was no significant difference in the putative virulence-associated factors studied among the different hosts. Moreover, strains isolated from a human and a cat from four familiar outbreaks presented a very similar profile of expression of these factors, reinforcing the zoonotic transmission of S. brasiliensis in Brazil and demonstrating the plasticity of this species in the production of virulence factors.

Sporothrix brasiliensis is the main agent of zoonotic sporotrichosis transmitted by domestic cats in South America. In humans, sporotrichosis commonly presents with cutaneous or lymphocutaneous lesions, and in cats, with multiple ulcerated skin lesions associated with enlarged lymph nodes and respiratory signs. Fungal virulence factors may affect the clinical presentation of the mycoses. Sporothrix spp. present some virulence factors. This study aims to compare 24 S. brasiliensis strains from 12 familiar outbreaks of cat-to-human transmitted sporotrichosis. Fungal growth in different substrates, thermotolerance, resistance to oxidative stress, and production of enzymes were evaluated. An invertebrate model of experimental infection was used to compare the virulence of the strains. The strains grew well on glucose and N-acetyl-D-glucosamine but poorly on lactate. Their thermotolerance was moderate to high. All strains were susceptible to hydrogen peroxide, and the majority produced hemolysins but not phospholipase and esterase. There was no significant difference in the putative virulence-associated factors studied among the different hosts. Moreover, strains isolated from a human and a cat from four familiar outbreaks presented a very similar profile of expression of these factors, reinforcing the zoonotic transmission of S. brasiliensis in Brazil and demonstrating the plasticity of this species in the production of virulence factors. [ABSTRACT FROM AUTHOR]

The West Nile Virus (WNV) NS2B-NS3 protease is an attractive target for the development of therapeutics against this arboviral pathogen. In the present investigation, the screening of a small library of fifty-eight synthetic compounds against the NS2-NB3 protease of WNV is described. The following groups of compounds were evaluated: 3-(2-aryl-2-oxoethyl)isobenzofuran-1(3H)-ones; eugenol derivatives bearing 1,2,3-triazolic functionalities; and indan-1,3-diones with 1,2,3-triazolic functionalities. The most promising of these was a eugenol derivative, namely 4-(3-(4-allyl-2-methoxyphenoxy)-propyl)-1-(2-bromobenzyl)-1H-1,2,3-triazole (35), which inhibited the protease with IC50 of 6.86 μmol L-1. Enzyme kinetic assays showed that this derivative of eugenol presents competitive inhibition behaviour. Molecular docking calculations predicted a recognition pattern involving the residues His51 and Ser135, which are members of the catalytic triad of the WNV NS2B-NS3 protease. [ABSTRACT FROM AUTHOR]

Background: The ubiquitination process can be reversed by deubiquitinating enzymes (DUBs). These proteases are involved in ubiquitin processing, in the recovery of modified ubiquitin trapped in inactive forms, and in the recycling of ubiquitin monomers from polyubiquitinated chains. The diversity of DUB functions is illustrated by their number and variety of their catalytic domains with specific 3D architectures. DUBs can be divided into five subclasses: ubiquitin C-terminal hydrolases (UCHs), ubiquitin-specific proteases (USPs or UBPs), ovarian tumour proteases (OTUs), Machado-Joseph disease proteases (MJDs) and JAB1/MPN/Mov34 metalloenzymes (JAMMs). Methods: Considering the role that the ubiquitin-proteasome system has been shown to play during the development of Schistosoma mansoni, our main goal was to identify and characterize SmUSPs. Here, we showed the identification of putative ubiquitin-specific proteases using bioinformatic approaches. We also evaluated the gene expression profile of representative USP family members using qRT-PCR. Results: We reported 17 USP family members in S. mansoni that present a conservation of UCH domains. Furthermore, the putative SmUSP transcripts analysed were detected in all investigated stages, showing distinct expression during S. mansoni development. The SmUSPs exhibiting high expression profiles were SmUSP7, SmUSP8, SmUSP9x and SmUSP24. Conclusion: S. mansoni USPs showed changes in expression levels for different life cycle stages indicating their involvement in cellular processes required for S. mansoni development. These data will serve as a basis for future functional studies of USPs in this parasite. [ABSTRACT FROM AUTHOR]

As a consequence of intense industrialization in the last few decades, the amount of agro-industrial wastes has increasing, where new forms of valorization are crucial. In this work, five residual biomasses from Maranhão (Brazil) were investigated as supports for immobilization of lipase from Thermomyces lanuginosus (TLL). The new biocatalysts BM-TLL (babaçu mesocarp) and RH-TLL (rice husk) showed immobilization efficiencies >98% and hydrolytic activities of 5.331 U g−1 and 4.608 U g−1, respectively, against 142 U g−1 by Lipozyme® TL IM. High esterification activities were also found, with 141.4 U g−1 and 396.4 U g−1 from BM-TLL and RH-TLL, respectively, against 113.5 U g−1 by TL IM. Results of porosimetry, SEM, and BET demonstrated BM and RH supports are mesoporous materials with large hydrophobic area, allowing a mixture of hydrophobic adsorption and confinement, resulting in hyperactivation of TLL. These biocatalysts were applied in the production of hexyl laurate, where RH-TLL was able to generate 94% conversion in 4 h. Desorption with Triton X-100 and NaCl confirmed that new biocatalysts were more efficient with 5 times less protein than commercial TL IM. All results demonstrated that residual biomass was able to produce robust and stable biocatalysts containing immobilized TLL with better results than commercial preparations. [ABSTRACT FROM AUTHOR]

The catechol (1,2-dihydroxybenzene) can be oxidized by enzymatic action, and then turned into quinone. Laccase (EC 1.10.3.2) is an enzyme produced mainly by fungi of white decomposition, which contains copper, and catalyzes the oxidation of phenolic substrates by coupling the reduction of O2 to water. The aim of this study is to evaluate the reutilization of Alginate Chitosan Laccase (ACL) beads for remediation of the catechol. In this study, the laccase was produced by the fungus Pycnoporus sanguineus. For the immobilization of the enzyme, 2% calcium alginate and the culture supernatant of the fungus cultivation were used. The mixture was dropped into a solution containing 2% CaCl2, for formation of beads. To ensure resistance enabling the reuse the beads, they were immersed in 0.3% chitosan solution. Enzymatic activity, optimum pH and optimum temperature were determined for the ACL beads and free enzyme. For reuse assay, 13 enzymatic cycles were realized, under agitation. As a result, we obtained optimum pH of 5.0 for free enzyme and ACL beads, optimum temperature of 40 °C for free enzyme and 50 °C for ACL beads. In the reuse test, it was shown that after 13 cycles of enzymatic activity, i.e. oxidation of catechol, it was stable until the 7Ω cycle. It can be concluded that the present study was effective for immobilization of laccase enzyme and oxidation of catechol. [ABSTRACT FROM AUTHOR]