28 results on '"Nonato, Maria Cristina"'
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2. Beyond publishing: introducing Interviews with authors
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Nonato, Maria Cristina, Raaij, Mark J. van, Agirre, Jon, Nonato, Maria Cristina, Raaij, Mark J. van, and Agirre, Jon
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What lies beyond publication in the life cycle of a successful scientific article? Were there any struggles that led the authors to alter their preferred course of action? Was the motivation for the research project personal or societal? Frustratingly, we rarely get any answers to these kinds of questions when we read an article. On the one hand, conferences might provide a rare opportunity to satisfy our curiosity – should we be so lucky to meet the authors in person. But with the frequency and dynamics of personal interactions radically changing at the start of the present decade, it is now possible to have a friendly chat with authors online without having to wait for a summer fixture.
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- 2024
3. Women in science symposium
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Crossman, David J. and Nonato, Maria Cristina
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- 2021
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4. Shaping the future of Acta Crystallographica F: unveiling our vision
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Nonato, Maria Cristina, primary
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- 2023
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5. Anti-Trypanosoma cruzi Activity, Mutagenicity, Hepatocytotoxicity and Nitroreductase Enzyme Evaluation of 3-Nitrotriazole, 2-Nitroimidazole and Triazole Derivatives
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Menozzi, Cheyene Almeida Celestino, primary, França, Rodolfo Rodrigo Florido, additional, Luccas, Pedro Henrique, additional, Baptista, Mayara dos Santos, additional, Fernandes, Tácio Vinício Amorim, additional, Hoelz, Lucas Villas Bôas, additional, Sales Junior, Policarpo Ademar, additional, Murta, Silvane Maria Fonseca, additional, Romanha, Alvaro, additional, Galvão, Bárbara Verena Dias, additional, Macedo, Marcela de Oliveira, additional, Goldstein, Alana da Cunha, additional, Araujo-Lima, Carlos Fernando, additional, Felzenszwalb, Israel, additional, Nonato, Maria Cristina, additional, Castelo-Branco, Frederico Silva, additional, and Boechat, Nubia, additional
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- 2023
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6. Welcoming Alejandro Buschiazzo, Dorothee Liebschner and Stephen Muench as Co‐editors of Acta Crystallographica F – Structural Biology Communications.
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Agirre, Jon, Nonato, Maria Cristina, and van Raaij, Mark J.
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COMPUTATIONAL biology , *MICROBIOLOGY , *MICROSCOPY , *EXPERTISE , *BIOLOGY - Abstract
The Section Editors welcome and introduce three new Co‐editors to the journal and summarize their expertise in computational structural biology, experimental structural biology and cryo‐electron microscopy. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Correction: Lesbon et al. Nucleocapsid (N) Gene Mutations of SARS-CoV-2 Can Affect Real-Time RT-PCR Diagnostic and Impact False-Negative Results. Viruses 2021, 13, 2474
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Lesbon, Jéssika Cristina Chagas, primary, Poleti, Mirele Daiana, additional, de Mattos Oliveira, Elisângela Chicaroni, additional, Patané, José Salvatore Leister, additional, Clemente, Luan Gaspar, additional, Viala, Vincent Louis, additional, Ribeiro, Gabriela, additional, Giovanetti, Marta, additional, de Alcantara, Luiz Carlos Junior, additional, Teixeira, Olivia, additional, Nonato, Maria Cristina, additional, de Lima, Loyze Paola Oliveira, additional, Martins, Antonio Jorge, additional, dos Santos Barros, Claudia Renata, additional, Marqueze, Elaine Cristina, additional, de Souza Todão Bernardino, Jardelina, additional, Moretti, Debora Botequio, additional, Brassaloti, Ricardo Augusto, additional, de Lello Rocha Campos Cassano, Raquel, additional, Mariani, Pilar Drummond Sampaio Correa, additional, Slavov, Svetoslav Nanev, additional, dos Santos, Rafael Bezerra, additional, Rodrigues, Evandra Strazza, additional, Santos, Elaine Vieira, additional, Borges, Josiane Serrano, additional, de La Roque, Debora Glenda Lima, additional, Kitajima, Joao Paulo, additional, Santos, Bibiana, additional, Assato, Patricia Akemi, additional, da Silva da Costa, Felipe Allan, additional, Banho, Cecilia Artico, additional, Sacchetto, Livia, additional, Moraes, Marilia Mazzi, additional, Palmieri, Melissa, additional, da Silva, Fabiana Erica Vilanova, additional, Grotto, Rejane Maria Tommasini, additional, Souza-Neto, Jayme A., additional, Nogueira, Mauricio Lacerda, additional, Coutinho, Luiz Lehman, additional, Calado, Rodrigo Tocantins, additional, Neto, Raul Machado, additional, Covas, Dimas Tadeu, additional, Kashima, Simone, additional, Elias, Maria Carolina, additional, Sampaio, Sandra Coccuzzo, additional, and Fukumasu, Heidge, additional
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- 2022
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8. Unraveling the structure and function of CdcPDE: A novel phosphodiesterase from Crotalus durissus collilineatus snake venom
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de Oliveira, Isadora Sousa, Pucca, Manuela Berto, Wiezel, Gisele Adriano, Cardoso, Iara Aimê, de Castro Figueiredo Bordon, Karla, Sartim, Marco Aurélio, Kalogeropoulos, Konstantinos, Ahmadi, Shirin, Baiwir, Dominique, Nonato, Maria Cristina, Sampaio, Suely Vilela, Laustsen, Andreas Hougaard, auf dem Keller, Ulrich, Quinton, Loïc, Arantes, Eliane Candiani, de Oliveira, Isadora Sousa, Pucca, Manuela Berto, Wiezel, Gisele Adriano, Cardoso, Iara Aimê, de Castro Figueiredo Bordon, Karla, Sartim, Marco Aurélio, Kalogeropoulos, Konstantinos, Ahmadi, Shirin, Baiwir, Dominique, Nonato, Maria Cristina, Sampaio, Suely Vilela, Laustsen, Andreas Hougaard, auf dem Keller, Ulrich, Quinton, Loïc, and Arantes, Eliane Candiani
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This study reports the isolation, structural, biochemical, and functional characterization of a novel phosphodiesterase from Crotalus durissus collilineatus venom (CdcPDE). CdcPDE was successfully isolated from whole venom using three chromatographic steps and represented 0.7% of total protein content. CdcPDE was inhibited by EDTA and reducing agents, demonstrating that metal ions and disulfide bonds are necessary for its enzymatic activity. The highest enzymatic activity was observed at pH 8-8.5 and 37 °C. Kinetic parameters indicated a higher affinity for the substrate bis(p-nitrophenyl) phosphate compared to others snake venom PDEs. Its structural characterization was done by the determination of the protein primary sequence by Edman degradation and mass spectrometry, and completed by the building of molecular and docking-based models. Functional in vitro assays showed that CdcPDE is capable of inhibiting platelet aggregation induced by adenosine diphosphate in a dose-dependent manner and demonstrated that CdcPDE is cytotoxic to human keratinocytes. CdcPDE was recognized by the crotalid antivenom produced by the Instituto Butantan. These findings demonstrate that the study of snake venom toxins can reveal new molecules that may be relevant in cases of snakebite envenoming, and that can be used as molecular tools to study pathophysiological processes due to their specific biological activities.
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- 2021
9. 3-Epiabruslactone A, a New Triterpene Lactone Isolated from Austroplenckia populnea
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Silva Grácia Divina de Fátima, Duarte Lucienir Pains, Paes Helena Clara da Silva, Sousa José Rêgo de, Nonato Maria Cristina, Portezani Paulo José, and Mascarenhas Yvonne Primerano
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Austroplenckia populnea ,Celastraceae ,3-epiabruslactone A ,structure elucidation ,Chemistry ,QD1-999 - Abstract
A new lactonic triterpene isolated from the heartwood of Austroplenckia populnea (Celastraceae) was characterized as 3alpha-hydroxyolean-12-en-29,22alpha-olide (the gamma-lactone of the 3alpha,22alpha-dihydroxyolean-12-en-29alpha-oic acid), the 3-epimer of the abruslactone A, on the basis of its spectral data, chemical transformations, and single crystal X-ray analysis.
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- 1998
10. The importance of international collaborations in science and structural biology.
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Nonato, Maria Cristina, van Raaij, Mark J., and Agirre, Jon
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COOPERATIVE research , *BIOLOGY - Abstract
The Acta Cryst. F – Structural Biology Communications Editors explain how important international collaborations are in science and structural biology. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Multimodal small-molecule screening for human prion protein binders
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Reidenbach, Andrew G., primary, Mesleh, Michael F., additional, Casalena, Dominick, additional, Vallabh, Sonia M., additional, Dahlin, Jayme L., additional, Leed, Alison J., additional, Chan, Alix I., additional, Usanov, Dmitry L., additional, Yehl, Jenna B., additional, Lemke, Christopher T., additional, Campbell, Arthur J., additional, Shah, Rishi N., additional, Shrestha, Om K., additional, Sacher, Joshua R., additional, Rangel, Victor L., additional, Moroco, Jamie A., additional, Sathappa, Murugappan, additional, Nonato, Maria Cristina, additional, Nguyen, Kong T., additional, Wright, S. Kirk, additional, Liu, David R., additional, Wagner, Florence F., additional, Kaushik, Virendar K., additional, Auld, Douglas S., additional, Schreiber, Stuart L., additional, and Minikel, Eric Vallabh, additional
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- 2020
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12. Structural, biochemical and biophysical characterization of recombinant human fumarate hydratase
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Ajalla Aleixo, Mariana A., primary, Rangel, Victor L., additional, Rustiguel, Joane K., additional, de Pádua, Ricardo A. P., additional, and Nonato, Maria Cristina, additional
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- 2019
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13. Discovery of Antimalarial Azetidine-2-carbonitriles That Inhibit P. falciparum Dihydroorotate Dehydrogenase
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Maetani, Micah, primary, Kato, Nobutaka, additional, Jabor, Valquiria A. P., additional, Calil, Felipe A., additional, Nonato, Maria Cristina, additional, Scherer, Christina A., additional, and Schreiber, Stuart L., additional
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- 2017
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14. Development of ML390: A Human DHODH Inhibitor That Induces Differentiation in Acute Myeloid Leukemia
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Lewis, Timothy A., primary, Sykes, David B., additional, Law, Jason M., additional, Muñoz, Benito, additional, Rustiguel, Joane K., additional, Nonato, Maria Cristina, additional, Scadden, David T., additional, and Schreiber, Stuart L., additional
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- 2016
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15. Full-length model of the human galectin-4 and insights into dynamics of inter-domain communication
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Rustiguel, Joane K., primary, Soares, Ricardo O. S., additional, Meisburger, Steve P., additional, Davis, Katherine M., additional, Malzbender, Kristina L., additional, Ando, Nozomi, additional, Dias-Baruffi, Marcelo, additional, and Nonato, Maria Cristina, additional
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- 2016
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16. Recombinant production, crystallization and crystal structure determination of dihydroorotate dehydrogenase fromLeishmania (Viannia) braziliensis
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Reis, Renata Almeida Garcia, primary, Lorenzato, Eder, additional, Silva, Valeria Cristina, additional, and Nonato, Maria Cristina, additional
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- 2015
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17. ThermoFMN - A Thermofluor Assay Developed for Ligand-Screening as an Alternative Strategy for Drug Discovery
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Pádua, Ricardo A. P., primary, Tomaleri, Giovani P., additional, Reis, Renata A. G., additional, David, Juliana S., additional, Silva, Valeria C., additional, Pinheiro, Matheus P., additional, and Nonato, Maria Cristina, additional
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- 2014
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18. Crystallization and preliminary X-ray diffraction analysis of recombinant chlorocatechol 1,2-dioxygenase fromPseudomonas putida
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Rustiguel, Joane Kathelen, primary, Pinheiro, Matheus Pinto, additional, Araújo, Ana Paula Ulian, additional, and Nonato, Maria Cristina, additional
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- 2011
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19. A rational protocol for the successful crystallization ofL-amino-acid oxidase fromBothrops atrox
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Alves, Raquel Melo, primary, Feliciano, Patricia Rosa, additional, Sampaio, Suely Vilela, additional, and Nonato, Maria Cristina, additional
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- 2011
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20. Recombinant production, crystallization and crystal structure determination of dihydroorotate dehydrogenase from Leishmania (Viannia) braziliensis.
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Reis, Renata Almeida Garcia, Lorenzato, Eder, Silva, Valeria Cristina, and Nonato, Maria Cristina
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DIHYDROOROTATE dehydrogenase ,RECOMBINANT antibodies ,LEISHMANIASIS ,CRYSTALLIZATION ,CRYSTAL structure - Abstract
The enzyme dihydroorotate dehydrogenase (DHODH) is a flavoenzyme that catalyses the oxidation of dihydroorotate to orotate in the de novo pyrimidine-biosynthesis pathway. In this study, a reproducible protocol for the heterologous expression of active dihydroorotate dehydrogenase from Leishmania (Viannia) braziliensis ( LbDHODH) was developed and its crystal structure was determined at 2.12 Å resolution. L. (V.) braziliensis is the species responsible for the mucosal form of leishmaniasis, a neglected disease for which no cure or effective therapy is available. Analyses of sequence, structural and kinetic features classify LbDHODH as a member of the class 1A DHODHs and reveal a very high degree of structural conservation with the previously reported structures of orthologous trypanosomatid enzymes. The relevance of nucleotide-biosynthetic pathways for cell metabolism together with structural and functional differences from the respective host enzyme suggests that inhibition of LbDHODH could be exploited for antileishmanicidal drug development. The present work provides the framework for further integrated in vitro, in silico and in vivo studies as a new tool to evaluate DHODH as a drug target against trypanosomatid-related diseases. [ABSTRACT FROM AUTHOR]
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- 2015
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21. Discovery of Antimalarial Azetidine-2-carbonitriles That Inhibit P. falciparum Dihydroorotate Dehydrogenase
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Maetani, Micah, Kato, Nobutaka, Jabor, Valquiria A. P., Calil, Felipe A., Nonato, Maria Cristina, Scherer, Christina A., and Schreiber, Stuart L.
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BRD7539 ,BRD9185 ,DHODH ,malaria ,diversity-oriented synthesis ,Plasmodium falciparum - Abstract
Dihydroorotate dehydrogenase (DHODH) is an enzyme necessary for pyrimidine biosynthesis in protozoan parasites of the genus Plasmodium, the causative agents of malaria. We recently reported the identification of novel compounds derived from diversity-oriented synthesis with activity in multiple stages of the malaria parasite life cycle. Here, we report the optimization of a potent series of antimalarial inhibitors consisting of azetidine-2-carbonitriles, which we had previously shown to target P. falciparum DHODH in a biochemical assay. Optimized compound BRD9185 (27) has in vitro activity against multidrug-resistant blood-stage parasites (EC50 = 0.016 μM) and is curative after just three doses in a P. berghei mouse model. BRD9185 has a long half-life (15 h) and low clearance in mice and represents a new structural class of DHODH inhibitors with potential as antimalarial drugs.
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- 2017
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22. A rational protocol for the successful crystallization of l-amino-acid oxidase from Bothrops atrox.
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Alves, Raquel Melo, Feliciano, Patricia Rosa, Sampaio, Suely Vilela, and Nonato, Maria Cristina
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CRYSTALLIZATION ,AMINO acids ,OXIDASES ,FER-de-lance ,X-ray diffraction measurement ,FLAVOPROTEINS - Abstract
Despite the valuable contributions of robotics and high-throughput approaches to protein crystallization, the role of an experienced crystallographer in the evaluation and rationalization of a crystallization process is still crucial to obtaining crystals suitable for X-ray diffraction measurements. In this work, the difficult task of crystallizing the flavoenzyme l-amino-acid oxidase purified from Bothrops atrox snake venom was overcome by the development of a protocol that first required the identification of a non-amorphous precipitate as a promising crystallization condition followed by the implementation of a methodology that combined crystallization in the presence of oil and seeding techniques. Crystals were obtained and a complete data set was collected to 2.3 Å resolution. The crystals belonged to space group P2
1 , with unit-cell parameters a = 73.64, b = 123.92, c = 105.08 Å, β = 96.03°. There were four protein subunits in the asymmetric unit, which gave a Matthews coefficient VM of 2.12 Å3 Da−1 , corresponding to 42% solvent content. The structure has been solved by molecular-replacement techniques. [ABSTRACT FROM AUTHOR]- Published
- 2011
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23. Caracterização estrutural e funcional das glutarredoxinas ditiolicas de Saccharomyces cerevisiae
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Discola, karen Fulan, Soares Netto, Luis Eduardo, 1964, Netto, Luis Eduardo Soares, 1964, Kobarg, Jörg, Garratt, Richard Charles, Laurindo, Francisco Rafael Martins, Nonato, Maria Cristina, Universidade Estadual de Campinas. Instituto de Biologia, Programa de Pós-Graduação em Biologia Funcional e Molecular, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Cristais, estrutura, morfologia e defeitos ,Glutaredoxin ,Saccharomyces cerevisiae ,Glutarredoxinas ,X-Ray crystal structure - Abstract
Orientador: Luis Eduardo Soares Netto Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia Resumo: Glutarredoxinas (Grxs) são pequenas oxidorredutases que possuem pelo menos um resíduo de cisteína conservado em seus sítios ativos e têm atividade dissulfeto redutase dependente de tiol. Embora Grxs estejam envolvidas em diversos processos celulares, como enovelamento protéico e proteção contra espécies reativas de oxigênio, poucos substratos biológicos dessas enzimas são conhecidos. Na levedura Saccharomyces cerevisiae, oito Grxs foram identificadas (ScGrx1-8); destas ScGrx1-2 são ditiólicas e possuem o motivo Cys-Pro-Tyr-Cys em seus sítios ativos. Ambas Grxs ditiólicas são citosólicas, embora ScGrx2 também seja encontrada na mitocôndria. Neste trabalho, mostramos que ScGrx2 possui atividade específica como oxidorredutase quinze vezes maior do que ScGrx1, embora estas enzimas compartilhem 64% de identidade e 85% de similaridade de seqüência. A análise cinética bi-substrato mostrou que ScGrx2 possui tanto um menor KM para glutationa quanto um maior turnover que ScGrx1. Com o intuito de compreender melhor estas diferenças bioquímicas, determinamos os valores de pKa da cisteína N-terminal (Cys27) dos sítios ativos destas duas proteínas e demonstramos que estes parâmetros não justificam a diferença de atividade observada. Tentando identificar características estruturais relacionadas a essa diferença de atividade, determinamos as estruturas cristalográficas de ScGrx2 na forma oxidada e do mutante ScGrx2-C30S ligado à glutationa a 2.05 e 1.91 Å de resolução, respectivamente, e comparamos estas estruturas com as estruturas de ScGrx1 descritas por Håkansson & Winther, 2007. As análises estruturais nos permitiram formular a hipótese de que substituições dos resíduos Ser23 e Gln52 de ScGrx1 por Ala23 e Glu52 em ScGrx2 poderiam modificar a capacidade da cisteína C-terminal do sítio ativo de atacar o dissulfeto misto formado entre a cisteína Nterminal e glutationa. Nossa hipótese foi testada através de ensaios enzimáticos com proteínas mutantes. Acreditamos que as diferenças funcionais e estruturais observadas entre ScGrx1 e ScGrx2 possam refletir em variações na especificidade por substratos e indicam que estas enzimas possuem funções biológicas não redundantes em S. cerevisiae. Abstract: Glutaredoxins (Grxs) are small thiol-dependent oxidoreductases with disulfide reductase activity endowed by at least one cysteine at their active sites. Although Grxs are implicated in many cellular processes, including protein folding and protection against reactive oxygen species, few of their targets are known. In the yeast Saccharomyces cerevisiae, eight Grxs isoforms were identified (ScGrx1-8). Two of them (ScGrx1-2) are dithiolic, possessing a conserved Cys-Pro-Tyr-Cys motif. Both dithiol glutaredoxins are cytosolic, however ScGrx2 is also located at the mitochondria. In spite of the fact that ScGrx1 and ScGrx2 share 85% of amino acid sequence similarity, we have shown that ScGrx2 is fifteen times more active as oxidoreductase than ScGrx1. Further characterization of the enzymatic activities through two-substrate kinetics analysis revealed that ScGrx2 possesses both a lower KM for glutathione and a higher turnover than ScGrx1. To better comprehend these biochemical differences, the pKa of the N-terminal active site cysteines (Cys27) of these two proteins were determined. Since the pKa values of ScGrx1 and ScGrx2 Cys27 residues are very similar, these parameters cannot account for the difference observed between their specific activities. In an attempt to better understand the mechanisms and differences between yeast dithiol Grxs activities, we elucidated the crystallographic structures of ScGrx2 in the oxidized state and of the ScGrx2-C30S mutant with a glutathionyl mixed disulfide at resolutions of 2.05 and 1.91 Å, respectively. Comparisons among these structures and those of ScGrx1 (Håkansson & Winther, 2007) provided insights into the remarkable functional divergence between these enzymes. We hypothesize that the substitutions of Ser23 and Gln52 in ScGrx1 by Ala23 and Glu52 in ScGrx2 can modify the capability of the active site C-terminal cysteine to attack the mixed disulfide between the N-terminal active site cysteine and the glutathione molecule. Mutagenesis studies supported this hypothesis. The observed structural and functional differences between ScGrx1 and ScGrx2 may reflect variations in substrate specificity and non-redundant biological functions. Doutorado Bioquímica Doutor em Biologia Funcional e Molecular
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- 2021
24. Desenvolvimento do fluxo de processamento automático de dados para Cristalografia Serial em Síncrotron na MANACÁ (Sirius)
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Rodrigues, Ana Carolina, 1996, Zeri, Ana Carolina de Mattos, Silva, Eduardo Granado Monteiro da, 1974, Nonato, Maria Cristina, Cezar, Júlio Criginski, Universidade Estadual de Campinas. Instituto de Física Gleb Wataghin, Programa de Pós-Graduação em Física, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Cristalografia serial em síncrotron ,Sirius Project ,Electronic data processing ,Projeto Sirius ,Serial synchrotron crystallography ,Processamento eletrônico de dados ,Python (Linguagem de programação de computador) ,Python (Computer program language) - Abstract
Orientadores: Ana Carolina de Mattos Zeri, Eduardo Granado Monteiro da Silva Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin Resumo: Manacá (MAcromolecular micro and NAno CrystAllography), primeira linha de luz em fase de comissionamento no Sirius (LNLS/CNPEM), é dedicada a diversos experimentos de cristalografia aplicadas em pequenas e macromoléculas, incluindo a recente técnica de cristalografia serial (SX). SX utiliza o feixe de microfoco e alto fluxo de fontes de luz avançadas, como o Sirius, para adquirir padrões únicos de difração de milhares de cristais por experimento, possivelmente, à temperatura ambiente. Um dos maiores desafios para SX é a união de conjuntos de dados parciais, aleatoriamente orientados no espaço recíproco, como se tivessem sido obtidos a partir da rotação de cristal único. Quanto ao dado final, o objetivo principal é extrair os melhores resultados dentro de uma variedade de combinações possíveis entre os subconjuntos de dado. Para solucionar isso, tem sido aplicados diferentes algoritmos, cada um com seus respectivos parâmetros a serem ajustados para toda coleta de dados. O objetivo dessa dissertação é fornecer uma rotina de processamento automático de dados para experimentos de SX realizados na Manacá. Construímos um script, em Python, que agirá como uma interface entre os usuários e os programas que estão sendo desenvolvidos para SX (CrystFEL, nXDS, cctbx.xfel, ccCluster, BLEND, xscale_isocluster, entre outros). Os usuários poderão chamar, de forma prática, diferentes programas de processamento, otimizar os parâmetros que melhor ajustem os seus dados, explorar visualmente as figuras de mérito e escolher as melhores opções de processamento. A fim de testar nossa rotina de processamento automático de dados, realizamos três experimen- tos durante o comissionamento científico da Manacá. Primeiramente, foram medidos 21 cristais de AmeGH128, no modo de oscilação (9.15 keV, tamanho de feixe variando de 20 a 60 µm), em 77K. Desse experimento, obtivemos um total de cerca de 64800 padrões de difração. Em seguida, cole- tamos 64 cristais de lisozima criocongelados, em modo grid-scan (12.69 keV, tamanho do feixe de 25 µm, fluxo de 10¹² ph/s). Nesse experimento, foram coletadas 2910 imagens no total. O mesmo experimento foi realizado em 20 cristais de lisozima em temperatura ambiente, utilizando um porta-amostra desenvolvido internamente pelo nosso grupo, selado com Kapton. Nessas condiçõs, nós obtivemos um total de 601 imagens. Os padrões de difrações obtidos foram usados como entrada para duas principais vias de proces- samento de SX: Hierarchical Cluster Analysis HCA (ccCluster) e imagens instantâneas (CrystFEL). Nosso script pôde indexar os padrões de difração com sucesso, de acordo com os parâmetros de célula unitária já conhecidos. Nosso fluxo de processamento de dados é versátil para verificação da qualidade dos dados e ajuste de parâmetros. Na rotina de imagens instantâneas, melhor qualidade final dos dados pode ser atingida, refinando a taxa de indexação e aumentando o número de cris- tais coletados. Todavia, a ferramenta de processamento de dados de SX é funcional e customizável para os usuários da Manacá. SX é uma promessa para o estudo de dinâmica de proteínas resolvida no tempo, e na descoberta de proteínas que são difíceis de cristalizar, como estruturas de proteínas de membrana. Possibilitar essa técnica na Manacá terá grande impacto em diversas áreas, desde descobrimento de drogas para tratamentos efetivos de doenças até otimização da produção de biocombustíveis renováveis Abstract: Manacá (MAcromolecular micro and NAno CrystAllography), first beamline in commissioning at Sirius (LNLS/CNPEM), is dedicated to a range of crystallography experiments applied to small and macro molecules, including the most recent technique of serial crystallography (SX). SX takes advantage of microfocus beam and higher flux from advanced light sources, such as Sirius, to acquire unique diffraction patterns from several tens of thousands of microcrystals per experiment, possibly, at room temperature. One of the biggest challenges for SX is to merge partial datasets, randomly oriented in the reciprocal space, as if they had been obtained from a single crystal rotation. Regarding final data, the main goal is to extract the best results from a range of all possible subdataset combination. To solve this, it has been applied different algorithms, each with their respective parameters that should be adjusted to every data collection. The aim of this dissertation is to provide an automated data processing pipeline for SX experiments on Manacá. We have built a script, in Python, that will act as an interface between users and new software being developed for SX (CrystFEL [5], nXDS, cctbx.xfel, ccCluster[3], BLEND[4], xscale isocluster, among others). Users will be able to, with minimal effort, call different data processing programs, adjust parameters that best fit their data, visually explore the figures of merit and choose the best data processing options. In order to test our data processing pipelines, we have performed three experiments during the Manacá’s scienctific commisioning. Firstly, it was measured 21 crystals of AmeGH128, in oscillation mode (9.15 keV, beam size varying from 20 to 60 µm ), at 77K. From that experiment, we obtained a total of around 64800 diffraction patterns. Afterwards, we collected 64 cryocooled lysozyme crystals, in grid-scan mode (12.69 keV, beam size 25 µm, flux at sample 10¹² ph/s). In this experiment, it was collected 2910 images in total. The same experiment was done on 20 lysozyme crystals at room-temperature, using an in-house build sample device, sealed with Kapton. In this condition, we obtained a total of 601 images. The diffraction patterns were used as an input for the two main branches of SX data processing: Hierarchical Cluster Analysis HCA (ccCluster) and snapshot images routine (CrystFEL). Our script could successfully index the diffraction patterns, according to the already known unit cell parameters. Our SX automatic data processing pipeline is versatile for immediate data quality verification and software parameters adjustments. In the snapshot routine, better final data quality might be achieved by tuning the indexing rate and increasing the number of crystals measured. Nevertheless, the SX data processing tool is functional and customizable for Manacá future users. Serial Crystallography is a huge promise for the study of time-resolved protein dynamics and in the revealing of proteins structures that are extremely difficult to crystallize, as membrane protein structures. Enabling this technique on Manacá will have a great impact in a variety of fields, from drug discovery for effective treatment of diseases to the optimization of renewable biofuels production Mestrado Física Mestra em Física CNPQ 143239/2019-8
- Published
- 2021
25. Produção heteróloga, purificação, caracterização funcional e predição estrutural do carregador mitochondrial de piruvato humano
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Neciosup Quesñay, José Edwin, 1988, Ambrosio, Andre Luís Berteli, Garratt, Richard Charles, Nonato, Maria Cristina, Farah, Shaker Chuck, Sgro, Germán Gustavo, Universidade Estadual de Campinas. Instituto de Biologia, Programa de Pós-Graduação em Biociências e Tecnologia de Produtos Bioativos, and UNIVERSIDADE ESTADUAL DE CAMPINAS
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Bioquímica ,Microscopia eletrônica de transmissão de varredura ,Pyruvic acid ,Membrane proteins ,Lipossomas unilamelares ,Proteínas de membrana ,Scanning transmission electron microscopy ,Unilamellar liposomes ,Biochemistry ,Ácido piruvico - Abstract
Orientador: Andre Luis Berteli Ambrosio Tese (doutorado) – Universidade Estadual de Campinas, Instituto de Biologia. Resumo: O piruvato é considerado o ponto central do metabolismo celular, chave para a geração de energia e blocos biossintéticos. Quando a oxidação do piruvato pelo ciclo do ácido cítrico é necessária, o piruvato citosólico deve ganhar acesso à matriz mitocondrial em um processo que se acredita envolver ativamente duas subunidades carreadoras de piruvato mitocondrial (MPC) organizadas em hetero-oligômeros. Desde 2012, quando as identidades moleculares de mamíferos MPC1 e MPC2 (e MPC3 em leveduras) foram finalmente apresentadas, vários estudos in vitro e in vivo revelaram uma interação inesperada entre duas ou mesmo três subunidades de proteínas que definem diferentes conjuntos funcionais, em um contexto metabólicos específicos; estes têm implicações claras na fisiologia da homeostase e em algumas doenças. No entanto, o mecanismo funcional baseado em estrutura de MPC permanece indefinido, apesar dos intensos esforços empregando ferramentas computacionais e técnicas experimentais de última geração. Nesta tese, a produção recombinante de MPC humano, através de uma estratégia de co-expressão, é incialmente descrita; no entanto, não foi observada formação substancial de complexos e, predominantemente, subunidades individuais foram purificadas. Em contraste com MPC1, que co-purifica com uma chaperona de levedura, demonstramos que os homo-oligômeros MPC2 promovem o transporte eficiente do piruvato em proteolipossomos. Os requisitos funcionais derivados e as características cinéticas do MPC2 assemelham-se aos demonstrados anteriormente para o MPC na literatura. De maneira distinta, a inibição química do transporte é observada apenas para um derivado de tiazolidinediona. O papel de transporte autônomo para MPC2 é validado em células, quando a expressão ectópica de MPC2 humano em levedura sem MPC endógeno estimulou o crescimento e aumentou o consumo de oxigênio celular. A detecção de várias espécies oligoméricas de MPC2 em isolados mitocondriais, proteínas purificadas e bicamadas lipídicas artificiais sugerem complexos funcionais de alta ordem (> 2 subunidades). Mudanças significativas no conteúdo da estrutura secundária de MPC2, conforme sondado por dicroísmo circular de radiação sincrotron, suportam ainda mais a interação entre a proteína e os ligantes. A cristalografia de raios X foi prejudicada pela incapacidade de se obter cristais adequados tanto, por difusão de vapor, quanto em fase cúbica lipídica, apesar da obtenção de condições iniciais promissoras. Por fim, a análise por crio-microscopia eletrônica de MPC2 reconstituído em nanodiscos de copolímeros sintéticos permitiu a proposição de uma montagem estequiométrica para o complexo. Coletivamente, nossos resultados fornecem bases para o papel independente do MPC2 na homeostase e doenças relacionadas ao metabolismo desregulado do piruvato e representam uma rota promissora para a determinação de um modelo atômico de alta resolução para MPC2 humano. Abstract: Pyruvate is considered the central hub in the cellular metabolism, key for the generation of both energy and biosynthetic blocks. When the oxidation of pyruvate by the citric acid cycle is required, cytosolic pyruvate must gain access to the mitochondrial matrix in a process thought to actively involve two mitochondrial pyruvate carrier (MPC) subunits assembled into heterotypic oligomers. Since 2012, when molecular identities of mammalian MPC1 and MPC2 (and MPC3 in yeast) were presented, range of in vitro and in vivo studies has since revealed an unexpected interplay between two or even three protein subunits that define different functional assemblies on a metabolic context-specific basis; these have clear implications on the physiology of homeostasis and diseases. However, the structure-based functional mechanism of MPC remains elusive, despite intensive efforts by different research groups that employ state-of-the-art computational tools and experimental techniques. In this thesis, the recombinant production of human MPC through a co-expression strategy is first described; nevertheless, substantial complex formation was not observed, and predominantly individual subunits were purified. In contrast to MPC1, which co-purifies with a host chaperone, we demonstrated that MPC2 homo-oligomers promote efficient pyruvate transport into proteoliposomes. The derived functional requirements and kinetic features of MPC2 resemble those previously demonstrated for MPC in the literature. Distinctly, chemical inhibition of transport is observed only for a thiazolidinedione derivative. The autonomous transport role for MPC2 is validated in cells when the ectopic expression of human MPC2 in yeast lacking endogenous MPC stimulated growth and increased oxygen consumption. Multiple oligomeric species of MPC2 across mitochondrial isolates, purified protein and artificial lipid bilayers suggest functional high-order complexes. Significant changes in the secondary structure content of MPC2, as probed by synchrotron radiation circular dichroism, further supports the interaction between the protein and ligands. X-ray crystallography was hampered by the inability to grow suitable crystals by vapor diffusion and in lipidic cubic phase, despite the successful obtention of promising hit conditions. Lastly, cryo-electron microscopy analysis of MPC2 reconstituted into synthetic copolymer nanodiscs allowed for the proposition of a stoichiometric assembly. Collectively, our results provide the initial framework for the independent role of MPC2 in homeostasis and diseases related to dysregulated pyruvate metabolism and may represent a promising route for the determination of a high-resolution atomic model for human MPC2. Doutorado Fármacos, Medicamentos e Insumos para Saúde Doutor em Ciências CAPES 001 FAPESP 2015/02734-7; 2019/02261-2
- Published
- 2020
26. Structural studies of the proteins Q4DV70 from Trypanosoma cruzi and mesothelin from Homo sapiens
- Author
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Camila Ramos dos Santos, Barbosa, João Alexandre Ribeiro Gonçalves, Aoyama, Hiroshi, Nonato, Maria Cristina, Fontes, Marcos Roberto de Mattos, Lima, Carmen Silvia Passos, Universidade Estadual de Campinas. Instituto de Biologia, Programa de Pós-Graduação em Biologia Funcional e Molecular, and UNIVERSIDADE ESTADUAL DE CAMPINAS
- Subjects
Thioredoxins ,Proteina Q4DV70 ,Trypanosoma cruzi ,Mesothelin ,Câncer ,Tiorredoxinas ,Q4DV70 protein ,Mesotelina - Abstract
Orientador: João Alexandre Ribeiro Gonçalves Barbosa Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia Resumo: Neste trabalho realizamos estudos estruturais com duas proteínas, a Q4DV70 de Trypanosoma cruzi e a mesotelina de Homo sapiens. O objetivo foi contribuir para a compreensão da função dessas proteínas, as quais possivelmente são importantes para a doença de Chagas e o câncer, respectivamente. A proteína Q4DV70 estava anotada no genoma de T. cruzi como hipotética conservada. Em nosso estudo, a proteína foi pela primeira vez detectada em amostras do parasita. Essa expressão ocorre na fase epimastigota, mas não na fase tripomastigota metacíclica, indicando que a proteína pode ter uma função importante no ciclo de vida do T. cruzi. A estrutura cristalográfica da Q4DV70 foi resolvida por substituição molecular e refinada com dados até 1,5 Å de resolução. Ela apresenta enovelamento tiorredoxina, formado por uma folha ß de 5 fitas cercada por duas hélices a de cada lado. As proteínas que apresentam maior identidade seqüencial e superposição estrutural com Q4DV70 são as tiorredoxinas e PDIs, oxidorredutases de pontes dissulfeto. Porém, as duas cisteínas do sítio ativo dessas proteínas estão substituídas por serinas em Q4DV70, o que impossibilita a função de formação, redução ou isomerização de pontes dissulfeto. Diversas tiorredoxina-like apresentam atividade chaperona independente da função oxidorredutase. Essa função está relacionada a regiões hidrofóbicas na superfície e/ou depende da presença de outro domínio. Q4DV70 é monomérica, composta apenas pelo domínio tiorredoxinalike, e não apresenta regiões hidrofóbicas em sua superfície. Além disso, não demonstrou capacidade de aumentar o enovelamento da GAPDH de T. cruzi. Esses resultados indicam que Q4DV70 não apresenta atividade chaperona. Mesotelina é uma proteína expressa em mesotélio normal e em diversos tipos de câncer, como mesotelioma, câncer de ovário e de pâncreas e leucemia mielóide aguda. Ela é considerada um marcador diagnóstico para esses cânceres e tem sido alvo para o desenvolvimento de drogas anti-tumor. Além disso, ela interage com MUC16, uma proteína presente na superfície de células de câncer de ovário. Apesar da reconhecida importância e uso da mesotelina, pouco se sabe sobre sua estrutura e função. A proteína foi purificada em condições desnaturantes e submetida ao re-enovelamento por diálise. Experimentos de dicroísmo circular, fluorescência e proteólise limitada comprovaram que a mesotelina foi corretamente re-enovelada. Essa amostra foi submetida a ensaios de cristalização, os quais resultaram em cristais que difrataram a baixa resolução. A estrutura de baixa resolução da mesotelina foi calculada a partir de dados de espalhamento de raios X a baixo ângulo e mostra que sua forma é alongada e curvada. O espectro de dicroísmo circular da mesotelina é típico de proteínas ricas em hélices a. Recentemente foi proposto que a estrutura da mesotelina é formada por uma estrutura em super-hélice, composta por repetições do tipo ARM, as quais apresentam 3 hélices a cada uma. Nossos resultados experimentais indicam que esse modelo teórico está correto. Proteólise limitada com quimotripsina resultou em um domínio estável de 20 kDa na região N-terminal da proteína. Esse domínio contém os 64 resíduos descritos como possível sítio de ligação a MUC16 e deve ser formado pelas 4 primeiras repetições do tipo ARM, de acordo com o modelo publicado. Abstract: In this work we carried out studies with two proteins, Q4DV70 from Trypanosoma cruzi and mesothelin from Homo sapiens. The aim was to help the understanding of the function of these proteins which possibly are important to Chagas disease and cancer, respectively. Q4DV70 protein was annotated in T. cruzi genome as a conserved hypothetical protein. In our studies, the protein was detected for the first time in parasite samples. Its expression occurs in the epimastigote form but not in the metacyclic trypomastigote form indicating that Q4DV70 is important for the pathogen life cycle. Q4DV70 crystal structure was solved by molecular replacement and refined with data to 1.5 Å maximum resolution. It shows a thioredoxin fold, formed by a five stranded ß-sheet flanked by two a-helixes in each side. The proteins more sequentially identical and better structurally superposed to Q4DV70 are thioredoxins and protein disulfide isomerases, which are disulfide oxidoreductases. However, the cysteine residues from CXXC motif of the active site are replaced by serines in Q4DV70, what prevents the function of formation, reduction and isomerization of disulfide bonds. Different thioredoxin-like proteins show chaperone activity independent of oxidoreductase function. This function is related to hydrophobic regions on the surface and/or is dependent of another domain. Q4DV70 is monomeric, composed only by thioredoxin-like domain and does not show hydrophobic regions on its surface. Moreover the protein does not increase the refolding of GAPDH from T. cruzi. These results indicate that Q4DV70 does not present chaperone activity. Mesothelin is a protein expressed in normal mesothelium and in different types of cancer, such as mesothelioma, ovarian cancer, acute myeloid leukemia and cancer of pancreas. It is considered a diagnostic marker for these cancers and it has been used in the development of antitumor drugs. Besides that, it binds to MUC16, a protein present on the surface of ovarian cancer cells. In spite of its recognized significance and use in cancer, little is known about its structure and function. The protein was purified under denaturing conditions and submitted to refolding by dialysis. Circular dichroism, fluorescence and limited proteolysis experiments confirmed that mesothelin was correctly refolded. This sample was submitted to crystallization trials that resulted in crystals which diffracted at low resolution. The low resolution structure of mesothelin was calculated from small angle X-ray scattering data and it shows an elongated and curved shape. The circular dichroism spectrum for mesothelin is typical of proteins that are rich in a-helixes. Recently it was proposed that mesothelin has a superhelix structure made by ARM repeats which are composed by 3 a-helixes each one. Our experimental results indicate that this theoretical model is correct. Limited proteolysis with chymotrypsin resulted in a stable domain of 20 kDa in the Nterminal region of the protein. This domain has the 64 residues described as the possible binding site for MUC16 and should be composed by the first four ARM repeats according to the model. Doutorado Bioquímica Doutor em Biologia Funcional e Molecular
- Published
- 2009
27. Nucleocapsid (N) Gene Mutations of SARS-CoV-2 Can Affect Real-Time RT-PCR Diagnostic and Impact False-Negative Results.
- Author
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Lesbon JCC, Poleti MD, de Mattos Oliveira EC, Patané JSL, Clemente LG, Viala VL, Ribeiro G, Giovanetti M, de Alcantara LCJ, Teixeira O, Nonato MC, de Lima LPO, Martins AJ, Dos Santos Barros CR, Marqueze EC, de Souza Todão Bernardino J, Moretti DB, Brassaloti RA, de Lello Rocha Campos Cassano R, Mariani PDSC, Slavov SN, Dos Santos RB, Rodrigues ES, Santos EV, Borges JS, de La Roque DGL, Kitajima JP, Santos B, Assato PA, da Silva da Costa FA, Banho CA, Sacchetto L, Moraes MM, Palmieri M, da Silva FEV, Grotto RMT, Souza-Neto JA, Nogueira ML, Coutinho LL, Calado RT, Neto RM, Covas DT, Kashima S, Elias MC, Sampaio SC, and Fukumasu H
- Subjects
- Brazil epidemiology, COVID-19 epidemiology, Coronavirus RNA-Dependent RNA Polymerase genetics, DNA Primers, False Negative Reactions, Genome, Viral genetics, Humans, Mutation, Phosphoproteins genetics, RNA, Viral genetics, SARS-CoV-2 genetics, COVID-19 diagnosis, COVID-19 Nucleic Acid Testing, Coronavirus Nucleocapsid Proteins genetics, SARS-CoV-2 isolation & purification
- Abstract
The current COVID-19 pandemic demands massive testing by Real-time RT-PCR (Reverse Transcription Polymerase Chain Reaction), which is considered the gold standard diagnostic test for the detection of the SARS-CoV-2 virus. However, the virus continues to evolve with mutations that lead to phenotypic alterations as higher transmissibility, pathogenicity or vaccine evasion. Another big issue are mutations in the annealing sites of primers and probes of RT-PCR diagnostic kits leading to false-negative results. Therefore, here we identify mutations in the N (Nucleocapsid) gene that affects the use of the GeneFinder COVID-19 Plus RealAmp Kit. We sequenced SARS-CoV-2 genomes from 17 positive samples with no N gene detection but with RDRP (RNA-dependent RNA polymerase) and E (Envelope) genes detection, and observed a set of three different mutations affecting the N detection: a deletion of 18 nucleotides (Del28877-28894), a substitution of GGG to AAC (28881-28883) and a frameshift mutation caused by deletion (Del28877-28878). The last one cause a deletion of six AAs (amino acids) located in the central intrinsic disorder region at protein level. We also found this mutation in 99 of the 14,346 sequenced samples by the Sao Paulo state Network for Pandemic Alert of Emerging SARS-CoV-2 variants, demonstrating the circulation of the mutation in Sao Paulo, Brazil. Continuous monitoring and characterization of mutations affecting the annealing sites of primers and probes by genomic surveillance programs are necessary to maintain the effectiveness of the diagnosis of COVID-19.
- Published
- 2021
- Full Text
- View/download PDF
28. Cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of recombinant human fumarase.
- Author
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Pereira de Pádua RA and Nonato MC
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- Amino Acid Sequence, Cloning, Molecular, Crystallization, Electrophoresis, Polyacrylamide Gel, Humans, Molecular Sequence Data, Fumarate Hydratase chemistry, Fumarate Hydratase isolation & purification, Recombinant Proteins chemistry, Recombinant Proteins isolation & purification, X-Ray Diffraction
- Abstract
Human fumarase (HsFH) is a well-known citric acid cycle enzyme and is therefore a key component in energy metabolism. Genetic studies on human patients have shown that polymorphisms in the fumarase gene are responsible for diseases such as hereditary leiomyomatosis and renal cell cancer. As a first step in unravelling the molecular basis of the mechanism of fumarase deficiency in genetic disorders, the HsFH gene was cloned in pET-28a, heterologously expressed in Escherichia coli, purified by nickel-affinity chromatography and crystallized using the vapour-diffusion technique. X-ray diffraction experiments were performed at a synchrotron source and the structure was solved at 2.1 Å resolution by molecular replacement.
- Published
- 2014
- Full Text
- View/download PDF
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