35 results on '"Ramos, Humberto J."'
Search Results
2. Molecular profiling of the Mahanarva spectabilis salivary glands and phytohormonal response of elephant grass
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Saraiva, Nayara B., Emidio, Nayara B., Vital, Camilo E., Gusmão, Michélia A. N., Marconato, Danielle G., Coutinho, Flaviane Silva, Pereira, Jorge Fernando, Auad, Alexander Machado, Faria-Pinto, Priscila, Ramos, Humberto J. O., and Oliveira, Maria Goreti Almeida
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- 2021
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3. Identification of metabolite traits from the current metabolomic approaches
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Omena-Garcia, Rebeca P., de Ávila Silva, Lucas, Vital, Camilo Elber, Araújo, Wagner L., Ramos, Humberto J. O., and Nunes-Nesi, Adriano
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- 2019
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4. Assessment of Triozoida limbata (Hemiptera: Triozidae) attacks: morphological and biochemical changes on Psidium guajava plants
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Picanço, Mayara M., primary, Silva, Ricardo S., additional, Azevedo, Aristea A., additional, Lima, Lucas L., additional, Ramos, Humberto J. O., additional, Souza, Og F. F., additional, Carmo, Flávia M. S., additional, and Picanço, Marcelo C., additional
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- 2022
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5. The Endoplasmic Reticulum Binding Protein BiP Displays Dual Function in Modulating Cell Death Events
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Carvalho, Humberto H., Silva, Priscila A., Mendes, Giselle C., Brustolini, Otávio J. B., Pimenta, Maiana R., Gouveia, Bianca C., Valente, Maria Anete S., Ramos, Humberto J. O., Soares-Ramos, Juliana R. L., and Fontes, Elizabeth P. B.
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- 2014
6. Inhibition constant and stability of tripeptide inhibitors of gut trypsin‐like enzyme of the soybean pest Anticarsia gemmatalis
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Almeida Barros, Rafael, primary, Meriño‐Cabrera, Yaremis, additional, Severiche Castro, José G., additional, Rodrigues da Silva Júnior, Neilier, additional, Schultz, Halina, additional, Andrade, Rafael J., additional, Aguilar de Oliveira, João V., additional, Ramos, Humberto J., additional, and Almeida Oliveira, Maria G., additional
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- 2022
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7. Production and Characterization of β-Glucanase Secreted by the Yeast Kluyveromyces marxianus
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Lopes, Mariana R., de Souza, Carlos J. A., Rodrigues, Marina Q. R. B., Costa, Daniela A., dos Santos, Ancély F., de Oliveira, Leandro L., Ramos, Humberto J. O., Guimarães, Valéria M., Silveira, Wendel B., Passos, Flávia M. L., and Fietto, Luciano G.
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- 2014
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8. Proteins from eggs of the spittlebug Mahanarva spectabilis (Hemiptera: Cercopidae) reveal clues about its diapause regulation
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Saraiva, Nayara B., primary, Auad, Alexander M., additional, Barros, Edvaldo, additional, Coutinho, Flaviane S., additional, Pereira, Jorge F., additional, Barros, Rafael A., additional, Ramos, Humberto J. O., additional, and Oliveira, Maria G. A., additional
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- 2021
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9. Intestinal proteases profiling from Anticarsia gemmatalis and their binding to inhibitors
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Silva‐Júnior, Neilier R., primary, Cabrera, Yaremis M., additional, Barbosa, Samuel L., additional, Barros, Rafael de A., additional, Barros, Edvaldo, additional, Vital, Camilo E., additional, Ramos, Humberto J. O., additional, and Oliveira, Maria Goreti A., additional
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- 2021
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10. Inhibition constant and stability of tripeptide inhibitors of gut trypsin‐like enzyme of the soybean pest Anticarsia gemmatalis.
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de Almeida Barros, Rafael, Meriño‐Cabrera, Yaremis, Severiche Castro, José G., Rodrigues da Silva Júnior, Neilier, Schultz, Halina, de Andrade, Rafael J., Aguilar de Oliveira, João V., de Oliveira Ramos, Humberto J., and de Almeida Oliveira, Maria G.
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- 2022
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11. Protein and phytohormone profiles of Mahanarva spectabilis salivary glands infesting different forages
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Monteiro, Luana P., primary, Silva Júnior, Neilier R., additional, Vital, Camilo E., additional, Barros, Rafael A., additional, Barros, Edvaldo, additional, Auad, Alexander M., additional, Pereira, Jorge F., additional, Ramos, Humberto J. de O., additional, and Oliveira, Maria G. de A., additional
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- 2021
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12. Identification of NH4+-regulated genes of Herbaspirillum seropedicae by random insertional mutagenesis
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Schwab, Stefan, Ramos, Humberto J., Souza, Emanuel M., Pedrosa, Fábio O., Yates, Marshall G., Chubatsu, Leda S., and Rigo, Liu U.
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- 2007
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13. Determination of bean nodule occupancy by Rhizobium tropici using the double gfp and gusA genetic markers constitutively expressed from a new broad-host-range vector
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Ramos, Humberto J. O., Souza, Emanuel M., Soares-Ramos, Juliana R. L., and Pedrosa, Fábio O.
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- 2007
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14. Approaches for the Design of Genetically Engineered Bacteria for Ecological Studies and Biotechnological Applications
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Ramos, Humberto J. O., primary, Yates, Marshall Geoffrey, additional, Pedrosa, Fábio O., additional, and Souza, Emanuel M., additional
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- 2013
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15. Proteins from eggs of the spittlebug Mahanarva spectabilis (Hemiptera: Cercopidae) reveal clues about its diapause regulation.
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Saraiva, Nayara B., Auad, Alexander M., Barros, Edvaldo, Coutinho, Flaviane S., Pereira, Jorge F., Barros, Rafael A., Ramos, Humberto J. O., and Oliveira, Maria G. A.
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DIAPAUSE ,HEMIPTERA ,EGGS ,MOLECULAR interactions ,PROTEIN metabolism ,HEAT shock proteins ,PROTEINS ,SERINE/THREONINE kinases - Abstract
Embryo development in eggs of the spittlebug Mahanarva spectabilis (Distant) (Hemiptera: Cercopidae) passes through four phases (known as S1 to S4) being stopped at S2 during diapause. Studies about the molecular basis of diapause in spittlebugs are nonexistent. Here, we analyzed proteins from non-diapausing (ND), diapausing (D) and post-diapausing (PD) eggs of the spittlebug M. spectabilis. In total, we identified 87 proteins where 12 were in common among the developmental and diapause phases and 19 remained as uncharacterized. Non-diapausing eggs (S2ND and S4ND) showed more proteins involved in information storage and processing than the diapausing ones (S2D). Eggs in post-diapausing (S4PD) had a higher number of proteins associated with metabolism than S2D. The network of protein interactions and metabolic processes allowed the identification of different sets of molecular interactions for each developmental and diapause phases. Two heat shock proteins (Hsp65 and Hsp70) along with two proteins associated with intracellular signaling (MAP4K and a serine/threonine-protein phosphatase) were found only in diapausing and/or post-diapausing eggs and are interesting targets to be explored in future experiments. These results shine a light on one key biological process for spittlebug survival and represent the first search for proteins linked to diapause in this important group of insects. [ABSTRACT FROM AUTHOR]
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- 2022
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16. Molecular profiling of the Mahanarva spectabilis salivary glands and phytohormonal response of elephant grass
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Saraiva, Nayara B., primary, Emidio, Nayara B., additional, Vital, Camilo E., additional, Gusmão, Michélia A. N., additional, Marconato, Danielle G., additional, Coutinho, Flaviane Silva, additional, Pereira, Jorge Fernando, additional, Auad, Alexander Machado, additional, Faria-Pinto, Priscila, additional, Ramos, Humberto J. O., additional, and Oliveira, Maria Goreti Almeida, additional
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- 2020
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17. Identification of -regulated genes of Herbaspirillum seropedicae by random insertional mutagenesis
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Schwab, Stefan, Ramos, Humberto J., Souza, Emanuel M., Pedrosa, Fábio O., Yates, Marshall G., Chubatsu, Leda S., and Rigo, Liu U.
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- 2007
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18. Intestinal proteolytic profile changes during larval development ofAnticarsia gemmataliscaterpillars
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Silva Júnior, Neilier R., primary, Vital, Camilo E., additional, Almeida Barros, Rafael, additional, Faustino, Verônica A., additional, Monteiro, Luana P., additional, Barros, Edvaldo, additional, Oliveira, Eugênio E., additional, Oliveira Ramos, Humberto J., additional, and Almeida Oliveira, Maria G., additional
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- 2019
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19. Broad range flavonoid profiling by LC/MS of soybean genotypes contrasting for resistance to Anticarsia gemmatalis (Lepidoptera: Noctuidae)
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Gómez, Jenny D., primary, Vital, Camilo E., additional, Oliveira, Maria G. A., additional, and Ramos, Humberto J. O., additional
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- 2018
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20. Genome of Herbaspirillum seropedicae Strain SmR1, a Specialized Diazotrophic Endophyte of Tropical Grasses
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Pedrosa, Fábio O., primary, Monteiro, Rose Adele, additional, Wassem, Roseli, additional, Cruz, Leonardo M., additional, Ayub, Ricardo A., additional, Colauto, Nelson B., additional, Fernandez, Maria Aparecida, additional, Fungaro, Maria Helena P., additional, Grisard, Edmundo C., additional, Hungria, Mariangela, additional, Madeira, Humberto M. F., additional, Nodari, Rubens O., additional, Osaku, Clarice A., additional, Petzl-Erler, Maria Luiza, additional, Terenzi, Hernán, additional, Vieira, Luiz G. E., additional, Steffens, Maria Berenice R., additional, Weiss, Vinicius A., additional, Pereira, Luiz F. P., additional, Almeida, Marina I. M., additional, Alves, Lysangela R., additional, Marin, Anelis, additional, Araujo, Luiza Maria, additional, Balsanelli, Eduardo, additional, Baura, Valter A., additional, Chubatsu, Leda S., additional, Faoro, Helisson, additional, Favetti, Augusto, additional, Friedermann, Geraldo, additional, Glienke, Chirlei, additional, Karp, Susan, additional, Kava-Cordeiro, Vanessa, additional, Raittz, Roberto T., additional, Ramos, Humberto J. O., additional, Ribeiro, Enilze Maria S. F., additional, Rigo, Liu Un, additional, Rocha, Saul N., additional, Schwab, Stefan, additional, Silva, Anilda G., additional, Souza, Eliel M., additional, Tadra-Sfeir, Michelle Z., additional, Torres, Rodrigo A., additional, Dabul, Audrei N. G., additional, Soares, Maria Albertina M., additional, Gasques, Luciano S., additional, Gimenes, Ciela C. T., additional, Valle, Juliana S., additional, Ciferri, Ricardo R., additional, Correa, Luiz C., additional, Murace, Norma K., additional, Pamphile, João A., additional, Patussi, Eliana Valéria, additional, Prioli, Alberto J., additional, Prioli, Sonia Maria A., additional, Rocha, Carmem Lúcia M. S. C., additional, Arantes, Olívia Márcia N., additional, Furlaneto, Márcia Cristina, additional, Godoy, Leandro P., additional, Oliveira, Carlos E. C., additional, Satori, Daniele, additional, Vilas-Boas, Laurival A., additional, Watanabe, Maria Angélica E., additional, Dambros, Bibiana Paula, additional, Guerra, Miguel P., additional, Mathioni, Sandra Marisa, additional, Santos, Karine Louise, additional, Steindel, Mario, additional, Vernal, Javier, additional, Barcellos, Fernando G., additional, Campo, Rubens J., additional, Chueire, Ligia Maria O., additional, Nicolás, Marisa Fabiana, additional, Pereira-Ferrari, Lilian, additional, da Conceição Silva, José L., additional, Gioppo, Nereida M. R., additional, Margarido, Vladimir P., additional, Menck-Soares, Maria Amélia, additional, Pinto, Fabiana Gisele S., additional, Simão, Rita de Cássia G., additional, Takahashi, Elizabete K., additional, Yates, Marshall G., additional, and Souza, Emanuel M., additional
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- 2011
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21. Conserved Threonine Residues within the A-Loop of the Receptor NIK Differentially Regulate the Kinase Function Required for Antiviral Signaling
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Santos, Anésia A., primary, Carvalho, Claudine M., additional, Florentino, Lilian H., additional, Ramos, Humberto J. O., additional, and Fontes, Elizabeth P. B., additional
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- 2009
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22. Determination of bean nodule occupancy by Rhizobium tropici using the double gfp and gusA genetic markers constitutively expressed from a new broad-host-range vector
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Ramos, Humberto J. O., primary, Souza, Emanuel M., additional, Soares-Ramos, Juliana R. L., additional, and Pedrosa, Fábio O., additional
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- 2006
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23. RBCS1 expression in coffee: Coffea orthologs, Coffea arabica homeologs, and expression variability between genotypes and under drought stress.
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Marraccini, Pierre, Freire, Luciana P., Alves, Gabriel S. C., Vieira, Natalia G., Vinecky, Felipe, Elbelt, Sonia, Ramos, Humberto J. O., Montagnon, Christophe, Vieira, Luiz G. E., Leroy, Thierry, Pot, David, Silva, Vânia A., Rodrigues, Gustavo C., and Andrade, Alan C.
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COFFEE ,PHOTOSYNTHESIS ,PLANT metabolism ,GENE expression ,DROUGHTS ,GENES - Abstract
Background: In higher plants, the inhibition of photosynthetic capacity under drought is attributable to stomatal and non-stomatal (i.e., photochemical and biochemical) effects. In particular, a disruption of photosynthetic metabolism and Rubisco regulation can be observed. Several studies reported reduced expression of the RBCS genes, which encode the Rubisco small subunit, under water stress. Results: Expression of the RBCS1 gene was analysed in the allopolyploid context of C. arabica, which originates from a natural cross between the C. canephora and C. eugenioides species. Our study revealed the existence of two homeologous RBCS1 genes in C. arabica: one carried by the C. canephora sub-genome (called CaCc) and the other carried by the C. eugenioides sub-genome (called CaCe). Using specific primer pairs for each homeolog, expression studies revealed that CaCe was expressed in C. eugenioides and C. arabica but was undetectable in C. canephora. On the other hand, CaCc was expressed in C. canephora but almost completely silenced in non-introgressed ("pure") genotypes of C. arabica. However, enhanced CaCc expression was observed in most C. arabica cultivars with introgressed C. canephora genome. In addition, total RBCS1 expression was higher for C. arabica cultivars that had recently introgressed C. canephora genome than for "pure" cultivars. For both species, water stress led to an important decrease in the abundance of RBCS1 transcripts. This was observed for plants grown in either greenhouse or field conditions under severe or moderate drought. However, this reduction of RBCS1 gene expression was not accompanied by a decrease in the corresponding protein in the leaves of C. canephora subjected to water withdrawal. In that case, the amount of RBCS1 was even higher under drought than under unstressed (irrigated) conditions, which suggests great stability of RBCS1 under adverse water conditions. On the other hand, for C. arabica, high nocturnal expression of RBCS1 could also explain the accumulation of the RBCS1 protein under water stress. Altogether, the results presented here suggest that the content of RBCS was not responsible for the loss of photosynthetic capacity that is commonly observed in water-stressed coffee plants. Conclusion: We showed that the CaCe homeolog was expressed in C. eugenioides and non-introgressed ("pure") genotypes of C. arabica but that it was undetectable in C. canephora. On the other hand, the CaCc homeolog was expressed in C. canephora but highly repressed in C. arabica. Expression of the CaCc homeolog was enhanced in C. arabica cultivars that experienced recent introgression with C. canephora. For both C. canephora and C. arabica species, total RBCS1 gene expression was highly reduced with WS. Unexpectedly, the accumulation of RBCS1 protein was observed in the leaves of C. canephora under WS, possibly coming from nocturnal RBCS1 expression. These results suggest that the increase in the amount of RBCS1 protein could contribute to the antioxidative function of photorespiration in water-stressed coffee plants. [ABSTRACT FROM AUTHOR]
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- 2011
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24. Intestinal proteolytic profile changes during larval development of Anticarsia gemmatalis caterpillars.
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Silva Júnior, Neilier R., Vital, Camilo E., Almeida Barros, Rafael, Faustino, Verônica A., Monteiro, Luana P., Barros, Edvaldo, Oliveira, Eugênio E., Oliveira Ramos, Humberto J., and Almeida Oliveira, Maria G.
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- 2020
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25. Tolerance of the soybean to drought: molecular responses of the overexpression of the chaperone BiP and interaction with endophytic fungus Pochonia Chlamydosporia
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Rodrigues, Juliano Mendonça, Fontes, Elizabeth Pacheco Batista, Ramos, Juliana Rocha Lopes Soares, Oliveira, Maria Goreti de Almeida, Freitas., Leandro Grassi de, and Ramos, Humberto J. de Oliveira
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Ramos, Humberto Josué de Oliveira,1969 ,Stress (Fisiologia) ,Soja - Resistencia a doença e pragas ,Bactérias fitopatogênicas ,Biologia Molecular ,Fungos - Abstract
CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Tolerância da soja a seca: respostas moleculares da superexpressão da chaperona BiP e da interação com fungo endofítico Pochonia chlamydosporia. Orientador: Humberto Josué de Oliveira Ramos. Coorientadores: Elizabeth Pacheco Batista Fontes, Juliana Rocha Lopes Soares Ramos, Maria Goreti de Almeida Oliveira e Leandro Grassi de Freitas. Plantas, por estarem inseridas em um ambiente dinâmico e complexo, estão expostas a diversas mudanças das condições ambientais que podem limitar o seu crescimento e produtividade. Estresses abióticos como escassez hídrica e secas prolongadas são um desafio, uma vez que tendem a se tornar cada vez mais frequentes devido a eventos climáticos extremos. Como maior produtor e exportador mundial de soja, a agricultura brasileira tem um interesse especial nos mecanismos de tolerância cruzada a estresses bióticos e abióticos em soja. Por isso, diversos estudos buscam obter mecanismos de adaptação e resistência vegetal a estresses ambientais com o melhoramento da produtividade agrícola e o mínimo de impacto ao meio ambiente. Uma das linhas de pesquisa visa a manipulação da chaperona molecular BiP em plantas transgênicas, cuja resposta ao estresse osmótico e do retículo endoplasmatico podem favorecer a tolerância à seca em soja. Entretanto, são boladas as informações sobre os efeitos da superexpressão de BiP no atraso na ativação da morte celular provocada por reação de hipersensitividade em situações de estresse biótico provocado pela bactéria não compatível Pseudomonas syringae pv. tomato. Outra linha de pesquisa, o uso de produtos biológicos baseados em organismos simbiontes da rizosfera vegetal que colonizam como raízes vegetais, dentre os quais o fungo nematófago endofítico Pochonia chlamydosporia pode estimular a capacidade da raiz de soja em explorar o solo ao redor favorecendo-a em condições de restrição hídrica. Neste trabalho, foi caracterizado o perfil morfológico, fisiológico e metabólico de genótipos contrastantes de soja quanto à tolerância a seca em resposta a interações bióticas. Foram analisadas a expressão de genes responsivos por RT-PCR, além da regulação diferencial de proteinas e fosfoproteinas responsivas à interação planta-bactéria no genótipo transgênico superexpressando BiP (C9) e (WT), sendo identificado por LC/MS- 2DE. Foram também adotados por LC-MS a abundância de fito-hormônios e alguns metabólitos especializados alvos em resposta à interação de soja com P. syringae pv. tomato e soja com P. chlamydosporia para determinar mudanças metabólicas básicas genótipos relacionados com a resposta à seca e/ou a resposta de defesa vegetal sob interações biológicas.Por sua vez, parâmetros morfofisiológicos de folhas, caule e raiz de genótipos tolerante a seca Embrapa48 e sensível a seca BR16 foram coletados ao longo do experimento planta-fungo. Concluiu-se que a via de síntese de flavonóides e isoflavonóides é uma das principais vias responsivas às inoculações com bactérias e com fungo em plantas, sendo determinante para a presença e contenção do hospedeiro. A resposta hipersensitiva bacteriana provocou uma expressão de genes que modulam a morte celular, sobretudo no genótipo transgênico, uma redução negativa de proteinas da fotossintese e uma regulação positiva de proteinas do metabolismo antioxidativo e do metabolismo dos fenilpropanoides e flavonóides, especialmente O-metiltransferases. Por fim, a interação bacteriana regulou positivamente os níveis de flavonoides e fitoalexinas em genótipos infectados. A presença do fungo, por sua vez, produziu um atraso de um dia na queda do potencial hídrico em ambos os genótipos contrastantes quanto a seca. O aumento do turgor foliar e como mudanças nos níveis de fito- hormônios, poliaminas e compostos fenólicos indicam que uma associação da planta ao fungo nas condições de déficit hídrico é inerente a cada genótipo, sendo que nenhum genótipo é tolerante a seca está ligada às propriedades hidráulicas dos vasos condutores. A presença do fungo promove mudanças morfológicas no sistema radicular e no sistema de vasos condutores da parte aérea em Embrapa48 e, em menor extensão, em BR16. Esses resultados podem ajudar a elucidar os mecanismos predominantes na tolerância cruzada de estresses bioticos e abioticos concomitantes, e como as plantas como utilizam para promover uma maior adaptação ao ambiente. Palavras-chave: Glycine max. Pseudomonas syringae patovar chlamydosporia. Estresses ambientais. Metabolômica. Proteômica. tomato. Pochonia Plants, being inserted in a dynamic and complex environment, are exposed to several changes in environmental conditions that can limit their growth and productivity. Abiotic stresses such as water scarcity and prolonged droughts are a challenge as they tend to become more and more frequent due to extreme weather events. As the world's largest producer and exporter of soybeans, Brazilian agriculture has a special interest in the mechanisms of cross-tolerance to biotic and abiotic stresses in soybeans. Therefore, several studies seek to obtain mechanisms for adaptation and plant resistance to environmental stresses with the improvement of agricultural productivity and minimal impact on the environment. One of the lines of research aims at manipulating the molecular chaperone BiP in transgenic plants, whose response to osmotic and endoplasmic reticulum stress can favor drought tolerance in soybean. However, information about the effects of BiP overexpression in the delay in the activation of cell death caused by hypersensitivity reaction in situations of biotic stress caused by the non-compatible bacteria Pseudomonas syringae pv. tomato. Another line of research, the use of biological products based on symbiotic organisms from the plant rhizosphere that colonize as plant roots, among which the endophytic nematophagus fungus Pochonia chlamydosporia can stimulate the capacity of the soybean root to explore the surrounding soil, favoring it in water restriction conditions. In this work, the morphological, physiological and metabolic profile of contrasting soybean genotypes regarding drought tolerance in response to biotic interactions was characterized. The expression of RT-PCR responsive genes was analyzed, as well as the differential regulation of proteins and phosphoproteins responsive to plant-bacteria interaction in the transgenic genotype overexpressing BiP (C9) and (WT), identified by LC/MS-2DE. The abundance of phytohormones and some specialized target metabolites in response to the interaction of soybean with P. syringae pv. tomato and soybean with P. chlamydosporia were also adopted by LC-MS to determine basic metabolic changes in genotypes related to droughtresponse and/or plant defense response under biological interactions. In turn, morphophysiological parameters of leaves, stem and root of drought-tolerant Embrapa48 and drought-sensitive BR16 genotypes were collected during the plant-fungus experiment. It was concluded that the flavonoid and isoflavonoid synthesis pathway is one of the main pathways responsive to inoculations with bacteria and fungus in plants, being crucial for the presence and containment of the host. The bacterial hypersensitive response caused an expression of genes that modulate cell death, especially in the transgenic genotype, a negative reduction of photosynthesis proteins and an upregulation of proteins from the antioxidant metabolism and the metabolism of phenylpropanoids and flavonoids, especially O-methyltransferases. Finally, bacterial interaction positively regulated the levels of flavonoids and phytoalexins in infected genotypes. The presence of the fungus, in turn, produced a one-day delay in the drop in water potential in both contrasting genotypes for drought. The increase in leaf turgor and changes in the levels of phytohormones, polyamines and phenolic compounds indicate that an association of the plant with the fungus under water deficit conditions is inherent to each genotype, and no genotype is drought tolerant is linked to the hydraulics properties of the conducting vessels. The presence of the fungus promotes morphological changes in the root system and in the aerial part vessel system in Embrapa48 and, to a lesser extent, in BR16. These results may help to elucidate the predominant mechanisms in the cross-tolerance of concomitant biotic and abiotic stresses, and how plants use them to promote greater adaptation to the environment. Keywords: Glycine max. Pseudomonas syringae pathovar tomato. Pochonia chlamydosporia. Environmental stresses. Metabolomics. Proteomics.
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- 2021
26. Differential defense responses of tropical grasses to Mahanarva spectabilis (Hemiptera: Cercopidae) infestation.
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Barros RA, Vital CE, Júnior NRS, Vargas MAS, Monteiro LP, Faustino VA, Auad AM, Pereira JF, Oliveira EE, Ramos HJO, and Oliveira MGA
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- Animals, Cattle, Genotype, Herbivory, Brachiaria, Hemiptera, Pennisetum
- Abstract
The spittlebugs Mahanarva spectabilis economically challenges cattle production of neotropical regions, due to its voracious feeding on tropical grasses. Here, we evaluated biochemical responses of the interaction between M. spectabilis and the widely cultivated tropical grasses Brachiaria spp. (i.e., brizantha and decumbens) and elephant grasses (cvs. Roxo de Botucatu and Pioneiro), regarding lipoxygenases, protease inhibitors, phytohormones, and proteolytic activities in the midgut of M. spectabilis. The M. spectabilis-infested grasses increased lipoxygenases activity, except for cv. Pioneiro. The levels of the phytohormones jasmonic and abscisic acids were similarly low in all genotypes and increased under herbivory. Furthermore, salicylic acid concentration was constitutively higher in Brachiaria sp., increasing only in spittlebug-infested B. decumbens. M. spectabilis infestations did not induce increases of protease inhibitors in any forage grass type. The trypsin activity remained unaltered, and the total proteolytic activity increased only in B. decumbens-fed insects. Our findings revealed that most forage grasses exposed to spittlebugs activate the lipoxygenases pathway, resulting in increased abscisic and jasmonic acids. However, greater amounts of these hormones do not induce protease inhibitory activity in response to spittlebug attack. This knowledge certainly helps to guide future projects aiming at reducing the impact of spittlebugs on forage production.
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- 2021
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27. Leaf metabolic profiles of two soybean genotypes differentially affect the survival and the digestibility of Anticarsia gemmatalis caterpillars.
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Gómez JD, Pinheiro VJM, Silva JC, Romero JV, Meriño-Cabrera Y, Coutinho FS, Lourenção AL, Serrão JE, Vital CE, Fontes EPB, Oliveira MGA, and Ramos HJO
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- Animals, Digestion, Genotype, Herbivory, Larva physiology, Lepidoptera physiology, Metabolome, Plant Leaves metabolism, Glycine max genetics
- Abstract
Insect pests such as Anticarsia gemmatalis cause defoliation and yield losses. Soybean breeding has obtained resistant genotypes, however the mechanism remains unknown. Studies indicated the presence of deterrents compounds in the resistant genotype IAC17, and their leaf metabolite profiles were compared to the susceptible genotype UFV105, which was elicited or not by caterpillar infestation. Cluster analysis indicated a significative distinction between these profiles as well as differences in plant defense pathways. Methylquercetins were constitutively present in the largest concentrations, specifically in the IAC17. Relationship between the resistance and the levels of phytohormones jasmonic acid, abscisic acid and salicylic acid was not observed. However, 1-aminocyclopropane -1carboxylic acid levels indicated that the ethylene may be involved in the constitutive biosynthesis of bioactive compounds. Extracts were added to the diets at three different concentrations to evaluate the effect on caterpillar survival. Lowest survival rates were observed when extracts from the resistant IAC 17 were used, at the lowest concentrations. Survival rates were not higher when IAC 17 infested by caterpillars were used. On the other hand, when extracts from the susceptible were used, the survival reductions were only observed in the highest extract concentrations. These supplementations of the diet reduced the digestive capacity, agreeing with the proteolytic activities, whereas malformations of the intestinal cells were dose dependent. The inhibitory effects persisted in higher dilutions only for the IAC17. Constitutive resistance was also explained by higher levels of protease inhibition. These results can be useful to elucidate the genes and cascades controlling the resistance., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)
- Published
- 2020
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28. Intestinal proteolytic profile changes during larval development of Anticarsia gemmatalis caterpillars.
- Author
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da Silva Júnior NR, Vital CE, de Almeida Barros R, Faustino VA, Monteiro LP, Barros E, de Oliveira EE, de Oliveira Ramos HJ, and de Almeida Oliveira MG
- Subjects
- Animals, Gastrointestinal Tract enzymology, Gastrointestinal Tract growth & development, Larva enzymology, Larva growth & development, Moths growth & development, Peptide Hydrolases classification, Moths enzymology, Peptide Hydrolases chemistry
- Abstract
Soybean is one of most consumed and produced grains in the world, and Anticarsia gemmatalis is a pest that causes great damage to this crop due to severe defoliation during its larval phase. Plants have mechanisms that lead to the inhibition of proteases in the intestine of these herbivores, hampering their development. Understanding this complex protease inhibitor is important for pest control. The objective of this study was to evaluate the enzymatic profiles of the intestinal proteases of the soybean caterpillar at different instars. For this, the proteolytic profile of the gut in the third, fourth, and fifth instars were analyzed. Irreversible inhibitors of proteases were separately incubated with A. gemmatalis enzyme extracts at the third, fourth, and fifth instar to assess the contribution of these proteases to total proteolytic activity. The enzymatic extracts were also evaluated with specific substrates to confirm changes in the specific activities of trypsin-like, chymotrypsin-like, and cysteine proteases at different instars. The results showed that the protease profile of A. gemmatalis gut changes throughout its larval development. The activity of cysteine proteases was more intense in the first instar. On the contrary, the serine proteases showed major activities in the late stages of the larval phase. Zymogram analysis and protein identification by liquid chromatography-mass spectrometry indicated serine protease as the main protease class expressed in the fifth instar. These results may shift the focus from the rational development of the protease inhibitor to A. gemmatalis and other Lepidoptera, as the expression of major proteases is not constant., (© 2019 Wiley Periodicals, Inc.)
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- 2020
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29. Human Exoproteome in Acute Apical Abscesses.
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Alfenas CF, Mendes TAO, Ramos HJO, Bruckner FP, Antunes HS, Rôças IN, Siqueira JF Jr, and Provenzano JC
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- Acute Disease, Humans, Periapical Abscess immunology, Proteins analysis, Suppuration metabolism, Periapical Abscess metabolism, Periapical Abscess microbiology, Proteins metabolism, Proteome
- Abstract
Introduction: An acute apical abscess is a severe response of the host to massive invasion of the periapical tissues by bacteria from infected root canals. Although many studies have investigated the microbiota involved in the process, information on the host factors released during abscess formation is scarce. The purpose of this study was to describe the human exoproteome in samples from acute apical abscesses., Methods: Fourteen pus samples were obtained by aspiration from patients with an acute apical abscess. Samples were subjected to protein digestion, and the tryptic peptides were analyzed using a mass spectrometer and ion trap instrument. The human proteins identified in this analysis were classified into different functional categories., Results: A total of 303 proteins were identified. Most of these proteins were involved in cellular and metabolic processes. Immune system proteins were also very frequent and included immunoglobulins, S100 proteins, complement proteins, and heat shock proteins. Polymorphonuclear neutrophil proteins were also commonly detected, including myeloperoxidases, defensins, elastases, and gelatinases. Iron-sequestering proteins including transferrin and lactoferrin/lactotransferrin were found in many samples., Conclusions: The human exoproteome included a wide variety of proteins related to cellular processes, metabolism, and immune response. Proteins involved in different mechanisms against infection, tissue damage, and protection against tissue damage were identified. Knowledge of the presence and function of these proteins using proteomics provides an insight into the complex host-pathogen relationship, the host antimicrobial strategies to fight infections, and the disease pathogenesis., (Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
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30. Differentially expressed genes and proteins upon drought acclimation in tolerant and sensitive genotypes of Coffea canephora.
- Author
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Marraccini P, Vinecky F, Alves GS, Ramos HJ, Elbelt S, Vieira NG, Carneiro FA, Sujii PS, Alekcevetch JC, Silva VA, DaMatta FM, Ferrão MA, Leroy T, Pot D, Vieira LG, da Silva FR, and Andrade AC
- Subjects
- Acclimatization, Coffea genetics, Droughts, Expressed Sequence Tags, Genotype, Molecular Sequence Data, Plant Proteins metabolism, Coffea physiology, Gene Expression Regulation, Plant, Plant Proteins genetics
- Abstract
The aim of this study was to investigate the molecular mechanisms underlying drought acclimation in coffee plants by the identification of candidate genes (CGs) using different approaches. The first approach used the data generated during the Brazilian Coffee expressed sequence tag (EST) project to select 13 CGs by an in silico analysis (electronic northern). The second approach was based on screening macroarrays spotted with plasmid DNA (coffee ESTs) with separate hybridizations using leaf cDNA probes from drought-tolerant and susceptible clones of Coffea canephora var. Conilon, grown under different water regimes. This allowed the isolation of seven additional CGs. The third approach used two-dimensional gel electrophoresis to identify proteins displaying differential accumulation in leaves of drought-tolerant and susceptible clones of C. canephora. Six of them were characterized by MALDI-TOF-MS/MS (matrix-assisted laser desorption-time of flight-tandem mass spectrometry) and the corresponding proteins were identified. Finally, additional CGs were selected from the literature, and quantitative real-time polymerase chain reaction (qPCR) was performed to analyse the expression of all identified CGs. Altogether, >40 genes presenting differential gene expression during drought acclimation were identified, some of them showing different expression profiles between drought-tolerant and susceptible clones. Based on the obtained results, it can be concluded that factors involved a complex network of responses probably involving the abscisic signalling pathway and nitric oxide are major molecular determinants that might explain the better efficiency in controlling stomata closure and transpiration displayed by drought-tolerant clones of C. canephora.
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- 2012
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31. MUMAL: multivariate analysis in shotgun proteomics using machine learning techniques.
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Cerqueira FR, Ferreira RS, Oliveira AP, Gomes AP, Ramos HJ, Graber A, and Baumgartner C
- Subjects
- Multivariate Analysis, Neural Networks, Computer, Sensitivity and Specificity, Algorithms, Artificial Intelligence, Chromatography, Liquid methods, Computational Biology methods, Proteins analysis, Proteomics methods, Tandem Mass Spectrometry methods
- Abstract
Background: The shotgun strategy (liquid chromatography coupled with tandem mass spectrometry) is widely applied for identification of proteins in complex mixtures. This method gives rise to thousands of spectra in a single run, which are interpreted by computational tools. Such tools normally use a protein database from which peptide sequences are extracted for matching with experimentally derived mass spectral data. After the database search, the correctness of obtained peptide-spectrum matches (PSMs) needs to be evaluated also by algorithms, as a manual curation of these huge datasets would be impractical. The target-decoy database strategy is largely used to perform spectrum evaluation. Nonetheless, this method has been applied without considering sensitivity, i.e., only error estimation is taken into account. A recently proposed method termed MUDE treats the target-decoy analysis as an optimization problem, where sensitivity is maximized. This method demonstrates a significant increase in the retrieved number of PSMs for a fixed error rate. However, the MUDE model is constructed in such a way that linear decision boundaries are established to separate correct from incorrect PSMs. Besides, the described heuristic for solving the optimization problem has to be executed many times to achieve a significant augmentation in sensitivity., Results: Here, we propose a new method, termed MUMAL, for PSM assessment that is based on machine learning techniques. Our method can establish nonlinear decision boundaries, leading to a higher chance to retrieve more true positives. Furthermore, we need few iterations to achieve high sensitivities, strikingly shortening the running time of the whole process. Experiments show that our method achieves a considerably higher number of PSMs compared with standard tools such as MUDE, PeptideProphet, and typical target-decoy approaches., Conclusion: Our approach not only enhances the computational performance, and thus the turn around time of MS-based experiments in proteomics, but also improves the information content with benefits of a higher proteome coverage. This improvement, for instance, increases the chance to identify important drug targets or biomarkers for drug development or molecular diagnostics.
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- 2012
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32. Antibiosis by Bacillus amyloliquefaciens ribonuclease barnase expressed in Escherichia coli against symbiotic and endophytic nitrogen-fixing bacteria.
- Author
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Ramos HJ, Souza EM, Soares-Ramos JR, and Pedrosa FO
- Subjects
- Bacterial Proteins, Cell Proliferation drug effects, Escherichia coli genetics, Ribonucleases genetics, Antibiosis physiology, Escherichia coli enzymology, Nitrogen Fixation physiology, Ribonucleases metabolism, Symbiosis physiology
- Abstract
A modified antibiosis assay was used to evaluate growth inhibition of symbiotic and endophytic bacteria by E. coli strains producing Bacillus amyloliquefaciens ribonuclease, barnase. Inhibition zones were only observed when the assays were performed in minimal medium agar. However, bacterial growth inhibition was not detected when using rich medium or susceptible strains expressing the ribonuclease inhibitor protein, barstar. Our results suggest that barnase may act as a broad range bacteriocin. The ecological significance of these results is discussed.
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- 2006
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33. A new system to control the barnase expression by a NifA-dependent promoter.
- Author
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Ramos HJ, Souza EM, Soares-Ramos JR, and Pedrosa FO
- Subjects
- Genetic Enhancement methods, Promoter Regions, Genetic genetics, Bacterial Proteins genetics, Bacterial Proteins metabolism, Gene Expression Regulation, Bacterial physiology, Protein Engineering methods, Ribonucleases genetics, Ribonucleases metabolism, Sinorhizobium meliloti enzymology, Sinorhizobium meliloti genetics, Transcription Factors genetics, Transcription Factors metabolism
- Abstract
Barnase is a potent ribonuclease widely used as a cytotoxic agent, tightly regulated by barstar to maintain cell viability. In this report, we describe a new composite regulatory system to control barnase cytotoxicity and expression, involving barstar and lacI genes under control of the NifA-, sigma54-dependent Sinorhizobium meliloti nifH promoter, and the barnase gene under control of the LacI-repressible ptac promoter. In this system, expression of thenifH promoter, activated by constitutively expressed NifA, resulted in constitutive synthesis of the LacI and barstar proteins. LacI, in turn, represses transcription of the barnase gene and barstar inhibits any ribonuclease activity. Full expression of the barnase gene induced by IPTG led to cell death. Control of barnase synthesis and activity could be achieved by regulating nifA expression and NifA protein activity by specific environmental signals.
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- 2005
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34. Endophytic Herbaspirillum seropedicae expresses nif genes in gramineous plants.
- Author
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Roncato-Maccari LD, Ramos HJ, Pedrosa FO, Alquini Y, Chubatsu LS, Yates MG, Rigo LU, Steffens MB, and Souza EM
- Abstract
Abstract The interactions between maize, sorghum, wheat and rice plants and Herbaspirillum seropedicae were examined microscopically following inoculation with the H. seropedicae LR15 strain, a Nif(+) (Pnif::gusA) mutant obtained by the insertion of a gusA-kanamycin cassette into the nifH gene of the H. seropedicae wild-type strain. The expression of the Pnif::gusA fusion was followed during the association of the diazotroph with the gramineous species. Histochemical analysis of seedlings of maize, sorghum, wheat and rice grown in vermiculite showed that strain LR15 colonized root surfaces and inner tissues. In early steps of the endophytic association, H. seropedicae colonized root exudation sites, such as axils of secondary roots and intercellular spaces of the root cortex; it then occupied the vascular tissue and there expressed nif genes. The expression of nif genes occurred in roots, stems and leaves as detected by the GUS reporter system. The expression of nif genes was also observed in bacterial colonies located in the external mucilaginous root material, 8 days after inoculation. Moreover, the colonization of plant tissue by H. seropedicae did not depend on the nitrogen-fixing ability, since similar numbers of cells were isolated from roots or shoots of the plants inoculated with Nif(+) or Nif(-) strains.
- Published
- 2003
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35. Monitoring Azospirillum-wheat interactions using the gfp and gusA genes constitutively expressed from a new broad-host range vector.
- Author
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Ramos HJ, Roncato-Maccari LD, Souza EM, Soares-Ramos JR, Hungria M, and Pedrosa FO
- Subjects
- Aluminum Silicates pharmacology, Azospirillum brasilense cytology, Azospirillum brasilense drug effects, Bacterial Adhesion genetics, Bacterial Adhesion physiology, Gene Expression, Gene Expression Regulation, Bacterial, Genes, Bacterial genetics, Genetic Markers genetics, Glucuronidase metabolism, Green Fluorescent Proteins, Indicators and Reagents, Luminescent Proteins analysis, Microscopy, Fluorescence methods, Plant Roots microbiology, Sensitivity and Specificity, Symbiosis, Azospirillum brasilense genetics, Azospirillum brasilense pathogenicity, Glucuronidase genetics, Luminescent Proteins genetics, Plasmids genetics, Triticum microbiology
- Abstract
To monitor the colonization of wheat roots by Azospirillum brasilense, we constructed several plasmids based on the pBBR1 replicon expressing the gfp and gusA genes constitutively. Both genes were placed under control of the gentamycin resistance gene promoter resulting in high levels of expression in Escherichia coli and A. brasilense. The constructed plasmids were stably maintained in A. brasilense strains even in the absence of selective pressure. The colonization of wheat plants grown under controlled conditions in sterilized vermiculite by A. brasilense strain FP2 (a Sp7-derivative) transconjugants containing these plasmids was monitored. Bacteria expressing GFP were easily observed in fresh plant material by fluorescence microscopy. Cell aggregates and single bacteria were visualized on the surfaces of young root zones, such as roots hairs and lateral roots. Large cellular clumps were observed at the points of lateral root emergence or at intercellular spaces of root epidermal cells 30 days after inoculation. Although we failed to detected bacteria in internal cortical and xylem tissues of wheat roots, the initial stage of endophytic colonization by A. brasilense may involve the sites detected in this work.
- Published
- 2002
- Full Text
- View/download PDF
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