A database for the taxonomic and phylogenetic identification of the genus Bradyrhizobium using multilocus sequence analysis.

Biological nitrogen fixation, with an emphasis on the legume-rhizobia symbiosis, is a key process for agriculture and the environment, allowing the replacement of nitrogen fertilizers, reducing water pollution by nitrate as well as emission of greenhouse gases. Soils contain numerous strains belonging to the bacterial genus Bradyrhizobium, which establish symbioses with a variety of legumes. However, due to the high conservation of Bradyrhizobium 16S rRNA genes - considered as the backbone of the taxonomy of prokaryotes - few species have been delineated. The multilocus sequence analysis (MLSA) methodology, which includes analysis of housekeeping genes, has been shown to be promising and powerful for defining bacterial species, and, in this study, it was applied to Bradyrhizobium, species, increasing our understanding of the diversity of nitrogen-fixing bacteria. Description: Classification of bacteria of agronomic importance is relevant to biodiversity, as well as to biotechnological manipulation to improve agricultural productivity. We propose the construction of an online database that will provide information and tools using MLSA to improve phylogenetic and taxonomic characterization of Bradyrhizobium, allowing the comparison of genomic sequences with those of type and representative strains of each species. Conclusion: A database for the taxonomic and phylogenetic identification of the Bradyrhizobium, genus, using MLSA, will facilitate the use of biological data available through an intuitive web interface. Sequences stored in the on-line database can be compared with multiple sequences of other strains with simplicity and agility through multiple alignment algorithms and computational routines integrated into the database. The proposed database and software tools are available at http://mlsa.cnpso.embrapa.br, and can be used, free of charge, by researchers worldwide to classify Bradyrhizobium, strains; the database and software can be applied to replicate the experiments presented in this study as well as to generate new experiments. The next step will be expansion of the database to include other rhizobial species.Edição dos Proceedings of the 10th International Conference of the Brazilian Association for Bioinformatics and Computational Biology (X-Meeting 2014), Belo Horizonte, Oct. 2014

Portais Web desenvolvidos no laboratório de bioinformática da Embrapa Soja.

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Conformational analysis of 2,2-difluoroethylamine hydrochloride: double gauche effect

The gauche effect in fluorinated alkylammonium salts is well known and attributed either to an intramolecular hydrogen bond or to an electrostatic attraction between the positively charged nitrogen and the vicinal electronegative fluorine atom. This work reports the effect of adding a fluorine atom in 2-fluoroethylamine hydrochloride on the conformational isomerism of the resulting 2,2-difluoroethylamine chloride (2). The analysis was carried out using NMR coupling constants in D2O solution, in order to mimic the equilibrium conditions in a physiological medium, in the gas phase and in implicit water through theoretical calculations. Despite the presence of sigma(CH)->sigma(*)(CF) and sigma(CH)->sigma(*)(CN) interactions, which usually rule the hyperconjugative gauche effect in 1,2-disubstituted ethanes, the most important forces leading to the double gauche effect (+NH3 in the gauche relationship with both fluorine atoms) in 2 are the Lewis-type ones. Particularly, electrostatic interactions are operative even in water solution, where they should be significantly attenuated, whereas hyperconjugation and hydrogen bond have secondary importance10877882CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçãosem informação2012/03933-5; 2011/11098-6; 2011/01170-

Abordagem computacional para a identificação de elementos cis-regulatórios no genoma da soja.

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Sistema Web para estimativas de perdas por seca na cultura da soja.

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Abordagem computacional para a identificação de elementos cis-regulatóriso no genoma da soja.

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Anti-Hepatitis C Virus Serology in Immune Thrombocytopenia: A Retrospective Analysis in 101 Patients.

Hepatitis C virus (HCV), an RNA virus, is known to be the major cause of post-transfusion non-A, non-B hepatitis. HCV can induce several expressions of autoimmunity, including both serological abnormalities and clinical disorders. The relationship between the HCV infection and anti-platelet autoimmunity has been occasionally described, but is still far from well-defined. We retrospectively analysed 101 serum specimens, collected between 1988 and 1994, from patients with immune thrombocytopenia (ITP) for the presence of anti-HCV antibodies. Eighty-seven patients were classified as having idiopathic, and 14 secondary ITP (4 systemic lupus erythematosus, 9 non-Hodgkin's lymphoma and 1 Evan's syndrome). Anti-HCV antibodies were determined by second generation tests (ELISA + RIBA). A specimen was considered positive for HCV antibodies in the presence of ELISA reactivity (sample optical density/cut-off > 1.00) accompanied by RIBA reactivity to at least one HCV specific antigen. 20 sera (20%) were positive, with a prevalence higher in secondary than in idiopathic ITP (43% vs. 16%, p < 0.05). No differences were found between anti-HCV positive and negative patients regarding gender, platelet count, platelet associated immunoglobulins, hepatitis B virus serology and liver enzyme profile. On the contrary, mean age was higher in the HCV positive vs HCV negative ones (58±18SD vs. 44±20yrs, p < 0.01), in keeping with the increasing prevalence of HCV infection with ageing. HCV positive patients, showed a poor response to treatment (platelet count lower than 50,000/μl after conventional medical therapy for immune thrombocytopenia) compared to anti-HCV negative ones, (50% versus 7.3%, p < 0.001). When we excluded patients who were exposed to risk factors for HCV infection after ITP diagnosis and before the serum collection, the prevalence of anti-HCV antibodies was not very different (17.6%) from that found in the series as a whole (19.8%). Our results seem to indicate that HCV infection may play a role in triggering several cases ITP, and moreover might constitute a negative prognostic factor for therapy response

Soybean gene express: plataforma para análise de expressão diferencial e bibliotecas substrativas de cDNA.

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