Geochemical constraints on the Hadean environment from mineral fingerprints of prokaryotes

The environmental conditions on the Earth before 4 billion years ago are highly uncertain, largely because of the lack of a substantial rock record from this period. During this time interval, known as the Hadean, the young planet transformed from an uninhabited world to the one capable of supporting, and inhabited by the first living cells. These cells formed in a fluid environment they could not at first control, with homeostatic mechanisms developing only later. It is therefore possible that present-day organisms retain some record of the primordial fluid in which the first cells formed. Here we present new data on the elemental compositions and mineral fingerprints of both Bacteria and Archaea, using these data to constrain the environment in which life formed. The cradle solution that produced this elemental signature was saturated in barite, sphene, chalcedony, apatite, and clay minerals. The presence of these minerals, as well as other chemical features, suggests that the cradle environment of life may have been a weathering fluid interacting with dry-land silicate rocks. The specific mineral assemblage provides evidence for a moderate Hadean climate with dry and wet seasons and a lower atmospheric abundance of CO2 than is present today.Fil: Novoselov, Alexey A.. Universidad de Concepción; ChileFil: Silva, Dailto. Universidade Estadual de Campinas; BrasilFil: Schneider, Jerusa. Universidade Estadual de Campinas; BrasilFil: Abrevaya, Ximena Celeste. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Chaffin, Michael S.. State University Of Colorado Boulder; Estados UnidosFil: Serrano, Paloma. Alfred Wegener Institute Helmholtz Centre For Polar And Marine Research,; AlemaniaFil: Navarro, Margareth Sugano. Universidade Estadual de Campinas; BrasilFil: Conti, Maria Josiane. André Tosello Institute; BrasilFil: Souza Filho, Carlos Roberto de. Universidade Estadual de Campinas; Brasi

Fatores que interferem durante o processo de fermentação natural das fatias de cubiu

This study aims to assess the effects of natural fermentation on the physical, physic-chemical and microbiological cubiu. Ripe cubiu undergone selection, peel, cut into four pieces, seeds removed and the slices were divided into two lots. One batch was subjected to blanching by immersion in water for 1 minute at 95 ° C and immediately bathed in ice water. Both were subjected to natural fermentation with increasing concentrations (2, 4, 6 and 8%) NaCl and 24 h time of immersion in each concentration. The process was monitored by moisture, pH, total acidity, sodium chloride, pectin and texture of the slices of cubiu. In relation to fresh fruit, money not increase the moisture and pH, decrease in total acidity and sodium and chloride did not significantly alter the texture. During the process of natural fermentation parameters moisture, acidity, texture and pH (control) were reduced from their values for pH (bleached) and sodium chloride was no increase in the values. The natural fermentation process was detected during the immersion of slices of cubiu pre treated or not in NaCl solutions. The physical and physic-chemical properties of slices cubiu were modified during the natural fermentation process, being more pronounced in slices.O objetivo foi avaliar os efeitos da fermentação natural nas características físicas, físico-químicas e microbiológicas do cubiu. Frutos maduros passaram por seleção, descasque, corte em quatro partes, retirada das sementes e as fatias foram divididas em dois lotes. Um dos lotes foi submetido ao branqueamento por imersão durante 1 minuto em água a 95° C e imediatamente em banho de água com gelo e outro lote não tive branqueamento. Ambos foram submetidos à fermentação natural com concentrações crescentes (2, 4, 6 e 8 %) de NaCl e tempo de 24 h de imersão em cada concentração. O processo foi monitorado pelas análises de umidade, pH, acidez total, cloreto de sódio, textura e pectina das fatias do cubiu. Em relação ao fruto in natura, o branqueamento acarretou aumento da umidade e pH, decréscimo da acidez total e do cloreto de sódio e não alterou significativamente a textura. Durante o processo de fermentação natural os parâmetros umidade, acidez total, textura e pH (controle) sofreram redução, para pH (branqueadas) e cloreto de sódio houve acréscimo. O processo de fermentação natural foi detectado durante a imersão das fatias do cubiu pré tratado ou não em soluções de cloreto de sódio (NaCl). As características físicas e físico-químicas das fatias de cubiu sofreram modificações no processo de fermentação natural, sendo mais acentuadas nas fatias pré tratadas

Enzimas hidrolíticas extracelulares de isolados de rizóbia nativos da Amazônia Central, Amazonas, Brasil

Legumes enrich the soil by contributing nitrogen through symbiotic biological nitrogen fixation by rhizobia bacteria. However, very little is known about the extracellular enzymatic profile of these microorganisms. In this context, the production of extracellular hydrolytic enzymes by indigenous strains of rhizobia in Central Amazonia was evaluated. This screening constitutes the first step in selecting indigenous microorganisms that are potentially exploitable as enzyme producers. Indigenous strains of rhizobia were screened for extracellular amylolytic, carboxymethylcellulolytic, lactolytic, lipolytic, pectinolytic and proteolytic activities on modified YMA. Ureolytic activity was detected on a urea-agar slant. Rhizobia strains isolated from cowpea nodules produced more enzymes than those isolated from soybean nodules. Out of all the extracellular hydrolytic enzymes evaluated, only pectinase was not detected in this study. The most frequent rhizobia enzymes were amylase (32.8%), protease (28.4%), urease (20.9%) and carboxymethylcellulase (9.0%). In this study, only amylase and protease enzymes varied significantly among rhizobia strains. INPA strains R-926 and R-915 showed the highest enzymatic levels for amylase (EI = 3.1) and protease (EI = 6.6), respectively. This paper showed some indigenous strains of rhizobia from Central Amazonia as promising sources of industrially relevant enzymes for biotechnological purposes

Produção de amilase por rizóbios, usando farinha de pupunha como substrato

Amylases are among the most important industrial enzymes and are of great significance in present-day biotechnology. Although they can be derived from various sources, enzymes from microbial sources are generally the most required by industry. Species of the genus Bacillus are considered to be the main sources of amylases, although screening for new microbial sources is increasing all over the world. The objective of the present study was to evaluate the production of amylase by indigenous rhizobia, using peach palm flour as substrate. In this study, a completely randomized experimental design was adopted with three replicates. Pearson's correlation coefficients were calculated for medium pH, extracellular protein, cellular biomass, mean colony diameter (MCD), mean halo diameter (MHD), enzymatic index (EI) and amylolytic activity variables from the bacteria selected. Out of the 19 rhizobia strains with amylolytic activity on modified YMA, seven (36.8%) strains showed "EI" ≥ 2,1, and they were considered as good producers of amylase. The "IE" presented by bacteria INPA R-987, R-950 and R-915B were significantly lower (p < 0.01) than those shown by the INPA R-926, R-975 and R-957. The amylolytic activity varied significantly (p < 0.01) among the rhizobia strains. INPA R-975 and R-926 strains presented, respectively, the highest (1.00 U.min-1.mL-1) and the lowest (0.31 U.min-1.mL-1) activity average. In general terms, the extracellular protein was correlated positively with "EI" (r = 0.52*; p < 0.05) and "MHD" (r = 0.55*; p < 0.05). The cellular biomass showed positive correlations with amylolytic activity (r = 0.55*; p < 0.05) and "MHD" (r = 0.54*; p < 0.05), and a negative with final pH medium (r = 0.93**; p < 0.01)

Electrophoresis and spectrometric analyses of adaptation-related proteins in thermally stressed Chromobacterium violaceum

Chromobacterium violaceum is a Gram-negative proteobacteria found in water and soil; it is widely distributed in tropical and subtropical regions, such as the Amazon rainforest. We examined protein expression changes that occur in C. violaceum at different growth temperatures using electrophoresis and mass spectrometry. The total number of spots detected was 1985; the number ranged from 99 to 380 in each assay. The proteins that were identified spectrometrically were categorized as chaperones, proteins expressed exclusively under heat stress, enzymes involved in the respiratory and fermentation cycles, ribosomal proteins, and proteins related to transport and secretion. Controlling inverted repeat of chaperone expression and inverted repeat DNA binding sequences, as well as regions recognized by sigma factor 32, elements involved in the genetic regulation of the bacterial stress response, were identified in the promoter regions of several of the genes coding proteins, involved in the C. violaceum stress response. We found that 30°C is the optimal growth temperature for C. violaceum, whereas 25, 35, and 40°C are stressful temperatures that trigger the expression of chaperones, superoxide dismutase, a probable small heat shock protein, a probable phasing, ferrichrome-iron receptor protein, elongation factor P, and an ornithine carbamoyltransferase catabolite. This information improves our comprehension of the mechanisms involved in stress adaptation by C. violaceum. © FUNPEC-RP

Effects of peeling methods on the quality of cubiu fruits

Cubiu (Solanum sessiliflorum Dunal) is an Amazonian Basin native fruit. Its importance comes from its high contents of pectin. Currently, processing technologies are necessary for the substitution of the traditional system (small crops and small-scale processing) for a larger scale system and thus increase the use of biodiversity and promote the implementation of Local Productive Arrangements of agribusiness in the Amazon. This research aims to evaluate the methods of peeling cubiu. Ripe fruits were divided into lots (150 each) and subjected to the following treatments: immersion in 2.5% NaOH boiling solution for 5 minutes, exposure to water vapor, and immersion in water at 96 ºC for 5, 10, 15 and 20 minutes. The peel released during heat treatment and immediately removed under running tap water. In the control treatment, the fruits were manually peeled (unheated) with a stainless steel knife. The treatments were evaluated for completeness and ease of peeling, tissue integrity, texture, and peroxidase activity. The immersion in 2.5% NaOH boiling solution (5 minutes) stood out as the best treatment since it inhibited the enzymatic browning and intensified the natural yellow color of the cubiu fruit and easily and fully peeled the whole fruit more rapidly without damaging its tissues. This treatment was chosen as the most advantageous because it can promote simultaneous peeling and bleaching. Therefore, it is recommended for cubiu industrial processing

Dementia in Latin America : paving the way towards a regional action plan

Regional challenges faced by Latin American and Caribbean countries (LACs) to fight dementia, such as heterogeneity, diversity, political instabilities, and socioeconomic disparities, can be addressed more effectively grounded in a collaborative setting based on the open exchange of knowledge. In this work, the Latin American and Caribbean Consortium on Dementia (LAC-CD) proposes an agenda for integration to deliver a Knowledge to Action Framework (KtAF). First, we summarize evidence-based strategies (epidemiology, genetics, biomarkers, clinical trials, nonpharmacological interventions, networking and translational research) and align them to current global strategies to translate regional knowledge into actions with transformative power. Then, by characterizing genetic isolates, admixture in populations, environmental factors, and barriers to effective interventions and mapping these to the above challenges, we provide the basic mosaics of knowledge that will pave the way towards a KtAF. We describe strategies supporting the knowledge creation stage that underpins the translational impact of KtAF

Factors that interfere in the process of natural fermentation of the cubiu slices

This study aims to assess the effects of natural fermentation on the physical, physic-chemical and microbiological cubiu. Ripe cubiu undergone selection, peel, cut into four pieces, seeds removed and the slices were divided into two lots. One batch was subjected to blanching by immersion in water for 1 minute at 95 ° C and immediately bathed in ice water. Both were subjected to natural fermentation with increasing concentrations (2, 4, 6 and 8%) NaCl and 24 h time of immersion in each concentration. The process was monitored by moisture, pH, total acidity, sodium chloride, pectin and texture of the slices of cubiu. In relation to fresh fruit, money not increase the moisture and pH, decrease in total acidity and sodium and chloride did not significantly alter the texture. During the process of natural fermentation parameters moisture, acidity, texture and pH (control) were reduced from their values for pH (bleached) and sodium chloride was no increase in the values. The natural fermentation process was detected during the immersion of slices of cubiu pre treated or not in NaCl solutions. The physical and physic-chemical properties of slices cubiu were modified during the natural fermentation process, being more pronounced in slices