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81.
Sergio Marangoni Jorge Ghiso Suely V. Sampaio Eliane C. Arantes José R. Giglio Benedito Oliveira Blas Frangione 《The protein journal》1990,9(5):595-601
The complete sequence of the toxin TsTX-VI from the venom of the scorpionTityus serrulatus Lutz and Mello is presented. The sequence has been determined by automated Edman analysis of the reduced and carboxymethylated protein as well as of the resulting peptides, obtained fromS. aureus protease and tryptic digestions. TsTX-VI is composed of 62 residues and has a calculated molecular weight of 6717. Homology studies with other scorpion toxins show that TsTX-VI is more similar to the Old World than to the North American scorpion toxins. The hydropathic index indicates that TsTX-VI is more hydrophobic than Ts-γ. Toxicity studies carried out in mice demonstrate that i.v. injection of TsTX-VI is unable to evoke the usual symptoms induced by the typical neurotoxins of this venom, but only a generalized allergic reaction. These properties are important in clarifying the relationship between primary structure and biological function of scorpion toxins. 相似文献
82.
Santiago HC Feng CG Bafica A Roffe E Arantes RM Cheever A Taylor G Vieira LQ Vierira LQ Aliberti J Gazzinelli RT Sher A 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(12):8165-8172
IFN-gamma is known to be required for host control of intracellular Trypanosoma cruzi infection in mice, although the basis of its protective function is poorly understood. LRG-47 is an IFN-inducible p47GTPase that has been shown to regulate host resistance to intracellular pathogens. To investigate the possible role of LRG-47 in IFN-gamma-dependent control of T. cruzi infection, LRG-47 knockout (KO) and wild-type (WT) mice were infected with the Y strain of this parasite, and host responses were analyzed. When assayed on day 12 after parasite inoculation, LRG-47 KO mice, in contrast to IFN-gamma KO mice, controlled early parasitemia almost as effectively as WT animals. However, the infected LRG-47 KO mice displayed a rebound in parasite growth on day 15, and all succumbed to the infection by day 19. Additional analysis indicated that LRG-47-deficient mice exhibit unimpaired proinflammatory responses throughout the infection. Instead, reactivated disease in the KO animals was associated with severe splenic and thymic atrophy, anemia, and thrombocytopenia not observed in their WT counterparts. In addition, in vitro studies revealed that IFN-gamma-stimulated LRG-47 KO macrophages display defective intracellular killing of amastigotes despite normal expression of TNF and NO synthetase type 2 and that both NO synthetase type 2 and LRG-47 are required for optimum IFN-gamma-dependent restriction of parasite growth. Together, these data establish that LRG-47 can influence pathogen control by simultaneously regulating macrophage-microbicidal activity and hemopoietic function. 相似文献
83.
Ana L. Arantes Joana I. Alves Alfons J. M. Stams M. Madalena Alves Diana Z. Sousa 《Microbial biotechnology》2018,11(4):639-646
The substitution of natural gas by renewable biomethane is an interesting option to reduce global carbon footprint. Syngas fermentation has potential in this context, as a diverse range of low‐biodegradable materials that can be used. In this study, anaerobic sludge acclimatized to syngas in a multi‐orifice baffled bioreactor (MOBB) was used to start enrichments with CO. The main goals were to identify the key players in CO conversion and evaluate potential interspecies metabolic interactions conferring robustness to the process. Anaerobic sludge incubated with 0.7 × 105 Pa CO produced methane and acetate. When the antibiotics vancomycin and/or erythromycin were added, no methane was produced, indicating that direct methanogenesis from CO did not occur. Acetobacterium and Sporomusa were the predominant bacterial species in CO‐converting enrichments, together with methanogens from the genera Methanobacterium and Methanospirillum. Subsequently, a highly enriched culture mainly composed of a Sporomusa sp. was obtained that could convert up to 1.7 × 105 Pa CO to hydrogen and acetate. These results attest the role of Sporomusa species in the enrichment as primary CO utilizers and show their importance for methane production as conveyers of hydrogen to methanogens present in the culture. 相似文献
84.
85.
James L Crainey Túllio RR da Silva Fernando Encinas Michel A Marín Ana Carolina P Vicente Sérgio LB Luz 《Memórias do Instituto Oswaldo Cruz》2016,111(1):79-81
We report here the first complete mitochondria genome of Onchocerca
volvulus from a focus outside of Africa. An O. volvulus
mitogenome from the Brazilian Amazonia focus was obtained using a combination of
high-throughput and Sanger sequencing technologies. Comparisons made between this
mitochondrial genome and publicly available mitochondrial sequences identified 46
variant nucleotide positions and suggested that our Brazilian mitogenome is more
closely related to Cameroon-origin mitochondria than West African-origin
mitochondria. As well as providing insights into the origins of Latin American
onchocerciasis, the Brazilian Amazonia focus mitogenome may also have value as an
epidemiological resource. 相似文献
86.
Rafael Tage Biaggio Ronivaldo Rodrigues da Silva Nathalia Gonsales da Rosa Rodrigo Simões Ribeiro Leite Eliane Candiani Arantes Tatiana Pereira de Freitas Cabral 《Preparative biochemistry & biotechnology》2016,46(3):298-304
Peptidases are important because they play a central role in pharmaceutical, food, environmental, and other industrial processes. A serine peptidase from Aspergillus terreus was isolated after two chromatography steps that showed a yield of 15.5%. Its molecular mass was determined to be 43 kD, by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). This peptidase was active between pH 5.0 to 8.0 and had maximum activity at pH 7.0, at 45°C. When exposited with 1 M of urea, the enzyme maintained 100% activity and used azocasein as substrate. The N-terminal (first 15 residues) showed 33% identity with the serine peptidase of Aspergillus clavatus ES1. The kinetics assays showed that subsite S2 did not bind polar basic amino acids (His and Arg) nonpolar acidic amino acids (Asp and Glu). The subsite S1 showed higher catalytic efficiency than the S2 and S3 subsites. 相似文献
87.
88.
Maysa Succi Tialfi Bergamin de Castro Ana Lívia Silva Galbiatti Lidia Maria Rebolho Batista Arantes Jéssika Nunes Gomes da Silva José Victor Maniglia Luiz Sérgio Raposo Érika Cristina Pavarino Eny Maria Goloni-Bertollo 《Molecular biology reports》2014,41(2):581-589
Folate is an essential nutrient with important roles in the synthesis, repair, and DNA methylation. Polymorphisms in genes encoding enzymes involved in folate metabolism can change these processes and modulate cancer development. We investigated DNMT3B C46359T (rs2424913) and SHMT1 C1420T (rs1979277) polymorphisms related to folate pathway in head and neck cancer (HNC) risk and the association of the disease with gender, risk factors and clinical histopathological parameters. A case–control study was conducted in 725 individuals (237 patients with HNC and 488 control individuals). Real-time PCR technique was performed for genotyping. Chi square and multiple logistic regression tests were used for statistical analysis. Male gender (OR 1.80; 95 % CI 1.11–2.94; P < 0.02) and tobacco consumption (OR 6.14; 95 % CI 4.13–9.13; P < 0.001) were associated with increased risk for this neoplasia. There were no significant associations between the polymorphisms and risk of disease, however, the tobacco and alcohol habits together showed association with SHMT1 C1420T polymorphism (OR 1.48; 95 % CI 1.08–2.03; P = 0.014). SHMT1 C1420T polymorphism was associated with larynx tumor (OR 0.48; 95 % CI 0.27–0.86; P < 0.05). In conclusion, tobacco habit and male gender can be predictors for HNC risk. SHMT1 C1420T and DNMT3B C46359T polymorphisms are not associated with HNC development in Brazilian population, however, SHMT1 C1420T polymorphism is less frequent in patients with primary site of tumor in larynx and more frequent in individuals who consume tobacco and alcohol together. Further studies involving gene–gene interactions in folate pathway in different populations can contribute to the understanding of the polymorphisms effect on HNC risk. 相似文献
89.
90.
Flaviano S. Martins Aparecida A. Silva Angélica T. Vieira Flávio H. F. Barbosa Rosa M. E. Arantes Mauro M. Teixeira Jacques Robert Nicoli 《Archives of microbiology》2009,191(8):623-630
The present work investigates some probiotic properties of four different microorganisms (Bifidobacterium animalis var. lactis BB-12, Escherichia coli EMO, Lactobacillus casei and Saccharomyces boulardii). In vitro and in vivo tests were carried out to compare cell wall hydrophobicity, production of antagonistic substances,
survival capacity in the gastrointestinal tract of germ-free mice without pathological consequence, and immune modulation
by stimulation of Küpffer cells, intestinal sIgA and IL-10 levels. In vitro antagonism against pathogenic bacteria and yeast
was only observed for the probiotic bacteria B. animalis and L. casei. The hydrophobic property of the cell wall was higher for B. animalis and E. coli EMO, and this property could be responsible for a better ability to colonize the gastrointestinal tract of germ-free mice.
Higher levels of sIgA were observed mainly for S. boulardii, followed by E. coli EMO and B. animalis, and only S. boulardii induced a significant higher level of IL-10. In conclusion, for a probiotic use, S. boulardii presented better characteristics in terms of immunomodulation, and B. animalis and L. casei for antagonistic substance production. The knowledge of the different probiotic properties could be used to choice the better
microorganism depending on the therapeutic or prophylactic application. 相似文献