In silico analysis and functional characterization of a leucine-rich repeat protein of leptospira interrogans

Pathogenic spirochetes of the genus Leptospira are the causative agent of leptospirosis, a widely disseminated zoonosis that affects humans and animals. The ability of leptospires to quickly cross host barriers causing infection is not yet fully understood. Thus, understanding the mechanisms of pathogenicity is important to combat leptospiral infection. Outer membrane proteins are interesting targets to study as they are able to interact with host molecules. Proteins containing leucine-rich repeat (LRR) domains are characterized by the presence of multiple regions containing leucine residues and they have putative functions related to host-pathogen interactions. Hence, the present study aimed to clone and express the recombinant protein encoded by the LIC11098 gene, an LRR protein of L. interrogans serovar Copenhageni. In silico analyses predicted that the target protein is conserved among pathogenic strains of Leptospira, having a signal peptide and multiple LRR domains. The DNA sequence encoding the LRR protein was cloned in frame into the pAE vector, expressed without mutations in Escherichia coli and purified by His-tag chromatography. Circular dichroism (CD) spectrum showed that the recombinant protein was predominantly composed of β-sheets. A dose-dependent interaction was observed with cellular and plasma fibronectins, laminin and the complement system component C9, suggesting a possible role of the protein encoded by LIC11098 gene at the initial stages of infection.

Lactational exposure to venlafaxine provokes late repercussions on reproductive parameters in male rat offspring.

Exposure to selective serotonin reuptake inhibitors can affect hormone-dependent processes, such as the brain sexual differentiation. Because the use of these antidepressants cause concern during lactation, we evaluated the possible effects of venlafaxine on lactational exposure and its late repercussions on reproductive parameters in male rats. Lactating rats were exposed to venlafaxine (3.85, 7.7, or 15.4 mg/kg/body weight; gavage), from lactational day 1 to 20. Venlafaxine and O-desmethylvenlafaxine residues were found in all milk samples of dams treated, demonstrating the lactational transfer of this antidepressant to the offspring. Although the maternal behavior was normal, the dams presented an increase in urea and uric acid levels in the groups treated with 7.7 and 15.4, respectively, as well as a spleen weight increased in the 3.85 and 15.4 groups. The male offspring showed a decrease in play behavior parameters in the intermediate dose group. Sperm analysis indicated a reduction in sperm motility in all treated groups. The androgen receptor expression in the hypothalamus was decreased in the highest dose group, although the sexual behavior had not been affected. In conclusion, venlafaxine was transferred through breast milk and promoted changes in play behavior, sperm quality, and hypothalamic androgen receptor (AR) content, which may indicate an incomplete masculinization of the brain of male offspring.

L-Asparaginase from Penicillium sizovae Produced by a Recombinant Komagataella phaffii Strain.

L-asparaginase is an important enzyme in the pharmaceutical field used as treatment for acute lymphoblastic leukemia due to its ability to hydrolyze L-asparagine, an essential amino acid synthesized by normal cells, but not by neoplastic cells. Adverse effects of L-asparaginase formulations are associated with its glutaminase activity and bacterial origin; therefore, it is important to find new sources of L-asparaginase produced by eukaryotic microorganisms with low glutaminase activity. This work aimed to identify the L-asparaginase gene sequence from Penicillium sizovae, a filamentous fungus isolated from the Brazilian Savanna (Cerrado) soil with low glutaminase activity, and to biosynthesize higher yields of this enzyme in the yeast Komagataella phaffii. The L-asparaginase gene sequence of P. sizovae was identified by homology to L-asparaginases from species of Penicillium of the section Citrina: P. citrinum and P. steckii. Partial L-asparaginase from P. sizovae, lacking the periplasmic signaling sequence, was cloned, and expressed intracellularly with highest enzymatic activity achieved by a MUT+ clone cultured in BMM expression medium; a value 5-fold greater than that obtained by native L-asparaginase in P. sizovae cells. To the best of our knowledge, this is the first literature report of the heterologous production of an L-asparaginase from a filamentous fungus by a yeast.

Filamentous Fungi Producing l-Asparaginase with Low Glutaminase Activity Isolated from Brazilian Savanna Soil.

l-asparaginase is an enzyme used as treatment for acute lymphoblastic leukemia (ALL) due to its ability to hydrolyze l-asparagine, an essential amino acid synthesized by normal cells unlike neoplastic cells. The adverse effects of l-asparaginase formulations are associated with its glutaminase activity and bacterial origin; therefore, it is important to find new sources of l-asparaginase-producing eukaryotic microorganisms with low glutaminase activity. This work evaluated the biotechnological potential of filamentous fungi isolated from Brazilian Savanna soil and plants for l-asparaginase production. Thirty-nine isolates were screened for enzyme production using the plate assay, followed by measuring enzymatic activity in cells after submerged fermentation. The variables influencing l-asparaginase production were evaluated using Plackett-Burman design. Cell disruption methods were evaluated for l-asparaginase release. Penicillium sizovae 2DSST1 and Fusarium proliferatum DCFS10 showed the highest l-asparaginase activity levels and the lowest glutaminase activity levels. Penicillium sizovae l-asparaginase was repressed by carbon sources, whereas higher carbon concentrations enhanced l-asparaginase by F. proliferatum. Maximum enzyme productivity, specific enzyme yield and the biomass conversion factor in the enzyme increased after Plackett-Burman design. Freeze-grinding released 5-fold more l-asparaginase from cells than sonication. This study shows two species, which have not yet been reported, as sources of l-asparaginase with possible reduced immunogenicity for ALL therapy.

Cryptococcus bromeliarum sp. nov., an orange-coloured basidiomycetous yeast isolated from bromeliads in Brazil.

During a survey of yeasts associated with the phylloplane of several bromeliad species in Itapuã Park in southern Brazil, we isolated four orange-coloured strains which were found to represent a novel anamorphic tremellaceous (Tremellales, Agaricomycotina, Basidiomycota) yeast species, Cryptococcus bromeliarum sp. nov. (type strain BI20(T) =CBS 10424(T) =NRRL Y-48112(T)). PCR-fingerprinting profiles of the four strains with primers M13 and (GTG)(5) were almost identical, which suggested conspecificity among the isolates. On the basis of D1/D2 26S rDNA sequence analysis, C. bromeliarum is phylogenetically closely related to other orange-coloured Cryptococcus species, namely Cryptococcus armeniacus, C. amylolyticus, C. tibetensis and C. cistialbidi, but differed from these species by at least six nucleotide substitutions and was thus considered a separate species. Physiological differences from C. armeniacus, C. amylolyticus and C. cistialbidi included the inability of C. bromeliarum to assimilate citrate and to form starch-like compounds. Differentiation from C. tibetensis can be achieved by the ability of the latter to assimilate ethylamine.

Synonymy of the yeast genera Moniliella and Trichosporonoides and proposal of Moniliella fonsecae sp. nov. and five new species combinations.

Analyses of nucleotide sequences from the D1/D2 domains of the large-subunit rDNA and phenotypic characteristics showed that the genera Moniliella and Trichosporonoides are members of a single, monophyletic clade that would be best represented by a single anamorphic genus. On the basis of taxonomic priority, we propose the transfer of the five species of the genus Trichosporonoides to the genus Moniliella. The description of the genus Moniliella is emended and the following new combinations are proposed: Moniliella madida comb. nov., Moniliella megachiliensis comb. nov., Moniliella nigrescens comb. nov., Moniliella oedocephalis comb. nov. and Moniliella spathulata comb. nov. In addition, ten strains representing a novel yeast species belonging to the Moniliella clade were isolated from flowers in Thailand, Cuba and Brazil. Analysis of the internal transcribed spacer and D1/D2 large-subunit rDNA sequences indicated that the isolates represent a single species that was distinct from other species of the Moniliella clade. The name Moniliella fonsecae sp. nov. is proposed to accommodate these strains. The type strain is BCC 7726(T) (=CBS 10551(T)).

A atenção à saúde bucal e o sistema de informações no município do Rio de Janeiro / The attention to the buccal health and the system of information in the city of Rio De Janeiro

Este estudo consiste em uma análise da implementação do Sistema de Informação em Saúde Bucal - SISB no Município do Rio de Janeiro. A exposição compreende três partes: 1) revisão das políticas e modelos de atenção odontológica no Brasil e no Rio de Janeiro; 2) exame dos Sistemas de Informações em Saúde do SUS e a inserção das informações relativas à saúde bucal nesses sistemas; e, 3) reconstituição dos Sistema de Informações em Saúde Bucal no Rio de Janeiro. Entre as conclusões aponta-se que o SISB ainda está em fase inicial de implementação. Todavia, já tem grande potencial para: subsidiar a tomada de decisões no campo da atenção odontológica; programar a produção dos serviços; construir indicadores de acompanhamento e avaliação, seja do ponto de vista administrativo, epidemiológico ou político.