The Structure of Isolated Synechococcus Strain WH8102 Carboxysomes as Revealed by Electron Cryotomography

Carboxysomes are organelle-like polyhedral bodies found in cyanobacteria and many chemoautotrophic bacteria that are thought to facilitate carbon fixation. Carboxysomes are bounded by a proteinaceous outer shell and filled with ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO), the first enzyme in the CO_2 fixation pathway, but exactly how they enhance carbon fixation is unclear. Here we report the three-dimensional structure of purified carboxysomes from Synechococcus species strain WH8102 as revealed by electron cryotomography. We found that while the sizes of individual carboxysomes in this organism varied from 114 nm to 137 nm, surprisingly, all were approximately icosahedral. There were on average ~250 RuBisCOs per carboxysome, organized into three to four concentric layers. Some models of carboxysome function depend on specific contacts between individual RuBisCOs and the shell, but no evidence of such contacts was found: no systematic patterns of connecting densities or RuBisCO positions against the shell's presumed hexagonal lattice could be discerned, and simulations showed that packing forces alone could account for the layered organization of RuBisCOs

Caracterização da microfauna de ciliados (Protista, Ciliophora) presentes em uma estação de tratamento de esgoto por processo de lodos ativados: avaliação da eficiência do tratamento

-Os sistemas de tratamento de esgotos por lodos ativados usam processos biológicos que reproduzem de certa maneira os processos naturais que ocorrem em um corpo de água após o lançamento de despejos. O princípio do processo baseia-se na oxidação bioquímica dos compostos orgânicos e inorgânicos presentes nos esgotos, mediada por uma microbiota diversificada e mantida em suspensão em um meio aeróbio. A eficiência depende da floculação da biomassa e da composição dos flocos formados, que incluem bactérias, fungos, protozoários e invertebrados, sendo esses dois últimos responsáveis pela manutenção da comunidade bacteriana, remoção de bactérias do grupo coliformes, redução da demanda bioquímica do oxigênio e floculação. Dados qualitativos da microfauna de protozoários e invertebrados podem indicar a eficiência do processo de depuração e a carga de esgoto no tanque de aeração em estações por lodos ativados. Entretanto a falta de especialistas e de atlas de identificação inviabilizam o uso desta microbiota . O presente trabalho teve como objetivo realizar um levantamento preliminar dos protozoários ciliados presentes em uma estação de tratamento de esgoto (ETE) por lodos ativados, a ETE Barreira do Triunfo, localizada na zona Norte do município de Juiz de Fora, Minas Gerais. Foram realizadas coletas do lodo ativado no tanque de aeração da estação e uma alíquota do material foi analisado in vivo no dia de coleta sob microscópio de campo claro, e outra alíquota foi utilizada para realização de culturas, com grãos de arroz com casca e água mineral. Os ciliados foram fotografados in vivo com auxílio de uma câmera digital Sony 7.2 acoplada a um microscópio BX 51 Olympus. Foram identificados os seguintes gêneros de protistas ciliados nas amostras analisadas no dia da coleta e nas culturas, os ciliados livre-natantes: Aspidisca, Euplotes, Paramecium, Lacrymaria, Spirostumum, Drepanomonas, Strombidium, Acineria, e os ciliados fixos: Vorticella, Epistylis, Acineta. Foram registrados ainda outros grupos de microorganismos que compõem a microbiota do lodo ativado: protistas flagelados (Peranema), protistas amebóides (Arcella, Euglypha e heliozoários), rotíferos, tardígrados, anelídeos e ácaros. Nas amostras analisadas no dia de coleta foi observada a predominância de ciliados hipotríquios (Aspidisca, Euplotes). Nos cultivos houve predominância de ciliados peritríquios (Epistylis, Vorticella) e notável redução dos ciliados hipotríquios. A predominância de ciliados hipotríquios observada no dia da coleta indica uma boa aeração e depuração no tanque de aeração analisado, sendo necessário, entretanto, a realização de estudo quantitativo elaborado para um diagnóstico preciso sobre a eficiência do processo de tratamento do esgoto da ETE Barreira do Triunfo. No presente estudo foi elaborado um atlas de identificação da microbiota presente no tanque de aeração da ETE Barreira do Triunfo que poderá ser usado pelos funcionários da companhia de saneamento municipal (CESAMA) responsáveis pelo monitoramento do lodo ativado

Avaliação da suscetibilidade a escorregamentos rasos com base na aplicação de estatística bivariada: resultados preliminares

O objetivo deste artigo foi definir a suscetibilidadea escorregamentos rasos do munícipio de Caraguatatuba apartir da análise estatística de parâmetros morfológicos. Paraa confecção dos mapas morfológicos de curvatura, aspecto,elevação e ângulo de encosta foi utilizado o SRTM de 30 m.A partir disso, foi realizada uma análise estatística bivariada,baseada no valor informativo. Tal índice é responsável porrelacionar classes morfológicas e cicatrizes deescorregamentos de eventos passados. Os resultadosmostraram que determinadas classes morfológicas tendem aser mais suscetíveis do que outras a ocorrência do processo,de maneira que se obteve uma taxa de acerto de 78% domapa final de suscetibilidade. Desta maneira, foi possívelverificar preliminarmente as classes preferenciais paraocorrência de escorregamentos na área, tornando importantea continuação dos estudos sobre o tema por meio daincorporação de outros parâmetros condicionantes deescorregamentos, como por exemplo a geologia.The aim of this paper was to define the shallowlandslides susceptibility on Caraguatatuba county, based onstatistical analysis of morphological parameters. Theproduction of morphological maps of curvature, aspect,hypsometry and slope were based on SRTM 30 m. From this,it was made a bivariate statistical analysis based oninformative value. Such index it is responsible to relatemorphological classes and shallow landslides from pastevents. The results showed that certain morphological classestend to be more susceptible to occurrence of the process. So,that a success rate of 78% of the final susceptibility map wasobtained. Thus, it was possible verify preliminary preferredclasses to landslide occurrence in the area, such resultdemonstrate the importance of future studies about landslidesand incorporation of other conditioning factors, such forexample geology

Evaluation of Susceptibility to Shallow Landslides Based on the Application of Bivared Statistics: Preliminary Results

The aim of this paper was to define the shallow landslides susceptibility on Caraguatatuba county, based on statistical analysis of morphological parameters. The production of morphological maps of curvature, aspect, hypsometry and slope were based on SRTM 30 m. From this, it was made an bivariate statistical analysis based on informative value. Such index it is responsible to relate morphological classes and shallow landslides from past events. The results showed that certain morphological classes tend to be more susceptible to occurrence of the process. So, that a success rate of 78% of the final susceptibility map was obtained. Thus, it was possible verify preliminary preferred classes to landslide occurrence in the area, such result demonstrate the importance of future studies about landslides and incorporation of other conditioning factors, such for example geology.O objetivo deste artigo foi definir a suscetibilidade a escorregamentos rasos do munícipio de Caraguatatuba a partir da análise estatística de parâmetros morfológicos. Para a confecção dos mapas morfológicos de curvatura, aspecto, elevação e ângulo de encosta foi utilizado o SRTM de 30 m. A partir disso, foi realizada uma análise estatística bivariada, baseada no valor informativo. Tal índice é responsável por relacionar classes morfológicas e cicatrizes de escorregamentos de eventos passados. Os resultados mostraram que determinadas classes morfológicas tendem a ser mais suscetíveis do que outras a ocorrência do processo, de maneira que se obteve uma taxa de acerto de 78% do mapa final de suscetibilidade. Desta maneira, foi possível verificar preliminarmente as classes preferenciais para ocorrência de escorregamentos na área, tornando importante a continuação dos estudos sobre o tema por meio da incorporação de outros parâmetros condicionantes de escorregamentos, como por exemplo a geologia

Intravenous glutamine decreases lung and distal organ injury in an experimental model of abdominal sepsis

Introduction The protective effect of glutamine, as a pharmacological agent against lung injury, has been reported in experimental sepsis; however, its efficacy at improving oxygenation and lung mechanics, attenuating diaphragm and distal organ injury has to be better elucidated. In the present study, we tested the hypothesis that a single early intravenous dose of glutamine was associated not only with the improvement of lung morpho-function, but also the reduction of the inflammatory process and epithelial cell apoptosis in kidney, liver, and intestine villi. Methods Seventy-two Wistar rats were randomly assigned into four groups. Sepsis was induced by cecal ligation and puncture surgery (CLP), while a sham operated group was used as control (C). One hour after surgery, C and CLP groups were further randomized into subgroups receiving intravenous saline (1 ml, SAL) or glutamine (0.75 g/kg, Gln). At 48 hours, animals were anesthetized, and the following parameters were measured: arterial oxygenation, pulmonary mechanics, and diaphragm, lung, kidney, liver, and small intestine villi histology. At 18 and 48 hours, Cytokine-Induced Neutrophil Chemoattractant (CINC)-1, interleukin (IL)-6 and 10 were quantified in bronchoalveolar and peritoneal lavage fluids (BALF and PLF, respectively). Results CLP induced: a) deterioration of lung mechanics and gas exchange; b) ultrastructural changes of lung parenchyma and diaphragm; and c) lung and distal organ epithelial cell apoptosis. Glutamine improved survival rate, oxygenation and lung mechanics, minimized pulmonary and diaphragmatic changes, attenuating lung and distal organ epithelial cell apoptosis. Glutamine increased IL-10 in peritoneal lavage fluid at 18 hours and bronchoalveolar lavage fluid at 48 hours, but decreased CINC-1 and IL-6 in BALF and PLF only at 18 hours. Conclusions In an experimental model of abdominal sepsis, a single intravenous dose of glutamine administered after sepsis induction may modulate the inflammatory process reducing not only the risk of lung injury, but also distal organ impairment. These results suggest that intravenous glutamine may be a potentially beneficial therapy for abdominal sepsis.Centres of Excellence Program (PRONEX-FAPERJ)Brazilian Council for Scientific and Technological Development (CNPq)Carlos Chagas FilhoRio de Janeiro State Research Supporting Foundation (FAPERJ)Sao Paulo State Research Supporting Foundation (FAPESP

Proteínas de reserva de acessos de coleção nuclear de arroz

O objetivo deste trabalho foi quantificar o conteúdo de proteína total de reserva dos 550 acessos da Coleção Nuclear de Arroz da Embrapa (CNAE), e avaliar o perfil proteico dos 20 acessos com maior teor de proteína em SDS-PAGE. Foi encontrado alto teor de proteína total de reserva (≥ 12,0%) em 103 acessos da CNAE, teor médio (11,9 a 9,0%) em 309 acessos e teor baixo (≤ 8,9%) em 138 acessos. Seis dos 20 acessos com maior teor de proteína de reserva apresentaram um padrão qualitativo diferencial de glutelina, que é a fração proteica de reserva mais abundante do grão de arroz. Há ampla variabilidade para o teor de proteína total de reserva do grão de arroz nos acessos da CNAE, a qual pode ser explorada por programas de melhoramento genético para aumentar o valor nutricional do arroz consumido no Brasil.The objective of this work was to quantify the total storage protein content of 550 accessions from Coleção Nuclear de Arroz da Embrapa (Embrapa Rice Core Collection – CNAE), and to evaluate the SDS-PAGE profile of the 20 accessions that showed the highest storage protein content. High storage protein content was found in 103 CNAE accessions (≥12.0%), intermediate content (11.9 to 9.0%) in 309, and low protein content (≤ 8.9%) in 138. Six out of the 20 accessions with the highest storage protein content showed a differential profile for glutelin, which is the most abundant rice storage protein fraction. There is a large variability of rice storage protein in CNAE accessions, which can be explored in breeding programs to increase the nutritional value of the rice consumed in Brazil

Investigation of the potential of deep eutectic solvents (DES) as alternative solvents in antimicrobial photodynamic therapy

Antimicrobial Photodynamic Therapy (aPDT) is gaining recognition as an effective approach for the photoinactivation of a broad spectrum of microorganisms [1,2]. Due to their apolar behavior, photosensitizers (PS) often have low solubility in aqueous media requiring the use of toxic organic solvents that are incompatible with their application in the field [4]. In this study, the potential of Deep Eutectic Solvents (DES) to prepare formulations of one chlorin (bearing five cationic charges) and two porphyrins (neutral THPP, and tetra cationic Tetra-Py(+)-Me) poorly water-soluble was investigated. To this purpose, formulations of each PS were prepared in DMSO and three DES (betaine:glycerol, proline:xylitol and betaine:citric acid) and their physio-chemical properties, cytotoxicity for mammalian cells, and photodynamic action towards Escherichia coli, as a gramnegative bacterium model, were evaluated. The physico-chemical experiments revealed that all PS were soluble in the selected DES. However, PS stability varied highly depending on the solvent used. In dark conditions, chlorin remained stable in DES formulations while strong aggregation was observed in DMSO. In contrast, THPP showed better stability in the former solvent. Tetra-cationic porphyrin was stable in the dark regardless of the solvent used, but upon irradiation, DES formulations increased this PS photostability. Regarding the biological experiments, betaine:glycerol and proline:xylitol formulations lacked toxicity towards mammalian cells and improved Tetra-Py(+)Me photodynamic activity against E. coli. On the other hand, betaine:citric acid formulation, although highly toxic to Vero cells, enhanced the photodynamic action of both THPP and Tetra-Py(+)-Me. Overall, these findings indicate that DES have a high potential to prepare formulations of PS with low solubility in aqueous solutions and, in some cases, can improve their antimicrobial photodynamic activity.info:eu-repo/semantics/publishedVersio

Deep Eutectic Solvents as alternative solvents in Antimicrobial Photodynamic Therapy

info:eu-repo/semantics/publishedVersio

Pathways for recent Cerrado soybean expansion : extending the soy moratorium and implementing integrated crop livestock systems with soybeans.

The Brazilian Soy Moratorium has effectively reduced forest conversion for soybeans in Amazonia. This has come at the expense of the region?s pasturelands, which have increasingly ceded space for compliant soy expansion. The question of extending the policy to the Cerrado, where recent soy expansion has come at the cost of ecologically valuable vegetation, plugs into a wider discussion on how to reconcile competing commodities on finite amounts of cleared area. Innovative management strategies that allow different land uses to coexist are urgently needed. Integrated crop-livestock systems with soybeans(ICLS)rotates beef and soy on the same area, and shows promise as a means to improve production, farmer benefit, and environmental impacts. Here we reconstruct historical land use maps to estimate Cerrado Soy Moratorium outcomes with benchmark years in 2008 and 2014, we then estimate additional production afforded by ICLS implementation between 2008 and 2014. We find that if a 2008 Cerrado Soy Moratorium were in place, 0.7 Mha of 2014 Cerrado soy area would currently be in violation of the policy. Roughly 96% of this acreage is found in Matopiba (82%) and Mato Grosso (14%)states, suggesting that adoption may have slowed recent production in these rapidly transforming soy centers, in contrast to central and southwestern Cerrado where there is more concentrated eligible expansion area. Changing the benchmark to 2014 could have added 0.7 Mha of eligible expansion area, though over 80% of these additions would be in states with the most 2008 eligible area (Distrito Federal, Mato Grosso, Maranh?o, Minas Gerais, Mato Grosso do Sul). Meanwhile, ICLS adoption could have added between 4.0 and 32 Mha of new soy land to the study area without additional clearing between 2008 and 2014, though this would depend on rigorous accompanying land zoning policy to guide implementation. The roughly 5 Mha of Cerrado soybean expansion that actually occurred between 2008 and 2014 could have been accommodated on 2008 suitable pasture area given an ICLS rotation frequency of every 6 years or less. Conservation estimates presented here represent the upper limit of what is possible, as our scenario modeling does not account for variables such as leakage, laundering, or rebound effects

Serum total and bone alkaline phosphatase levels and their correlation with serum minerals over the lifespan of sheep

This study aimed to assess serum total alkaline phosphatase (ALP) and its bone isoform (BALP) levels during the ageing and in different physiologic states of sheep, in order to expand the knowledge about the variation of these biomarkers over the sheep lifespan. Ninety female sheep were divided into nine groups of various ages and physiological states (dry, lactation and pregnancy). Serum ALP, BALP and mineral levels were determined by commercial immunoassay, molecular absorbance spectrophotometry and chemical luminescence for BALP determination. Serum ALP and BALP decreased as sheep aged, and no statistically significant differences were obtained between ewes in different physiologic states. The continuous decline of serum BALP concentration along the sheep lifespan, namely in mature and old sheep, is a sign of decreasing bone turnover associated with ageing. Serum calcium concentrations increased slightly until 2 years of age and then showed a tenuous but statistically significant decrease in mature sheep, while serum phosphorus maintained an uninterrupted decrease as sheep matured. The knowledge of serum values of bone biomarkers throughout the sheep lifespan may be useful in preclinical orthopaedic research studies and for animal science studies using sheep.Cristina P. Sousa acknowledges the Portuguese Foundation for Science and Technology for her PhD scholarship SFRH/BD/45018/2008