Production and characterization of collagenase by Penicillium sp. UCP 1286 isolated from Caatinga soil

A new Penicillium sp. strain isolated from the soil of Caatinga, a Brazilian Biome (UCP 1286) was selected for collagenase production. Fermentation system allowing obtention of collagenolytic activity about 2.7 times higher than existing data, with the highest values of collagenolytic and specific activity (379.80 U/mL, 1460.77 U/mg, respectively), after 126 hours. Applying a factorial design, enzyme production was increased by about 65% compared to the preliminary results. The factorial design demonstrated the existence of two factors with statistical significance on the production of the enzyme: pH and temperature, both with negative effects. Enzyme was found to be more active at pH 9.0 and 37 °C, and also to be very stable in comparison with the collagenase produced by other microorganisms. The enzyme seems to belong to collagenolytic serine proteases family. Concerning the substrate specificity, it was observed that the highest enzyme activity corresponds to azocoll, there was no relevant activity on azocasein and the enzyme showed to be more specific to type V collagen and gelatin than the commercial colagenase produced by Clostridium histolyticum. Major band observed at electrophoresis was approximately 37 kDa. Zymogram analysis confirmed the collagenolytic activity. All data indicates this enzyme as promising biotechnology product.This work was supported by Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco (FACEPE) (IBPG-0137-2.08/12) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). Sara Silvério also acknowledges her post-doc grant (SFRH/BPD/88584/2012) from FCT (Fundação para a Ciência e a Tecnologia), Portugal

Purification and characterization of a collagenase from Penicillium sp. UCP 1286 by polyethylene glycol-phosphate aqueous two-phase system

Collagenases are proteolytic enzymes capable of degrading both native and denatured collagen, reported to be applied in industrial, medical and biotechnological sectors. Liquid-liquid extraction using aqueous two-phase system (ATPS) is one of the most promising bioseparation techniques, which can substitute difficult solid-liquid separation processes, offering many advantages over conventional methods including low-processing time, low-cost material and low-energy consumption. The collagenase produced by Penicillium sp. UCP 1286 showed a stronger affinity for the bottom salt-rich phase, where the highest levels of collagenolytic activity were observed at the center point runs, using 15.0% (w/w) PEG 3350 g/mol and 12.5% (w/w) phosphate salt at pH 7.0 and concentration. The enzyme was characterized by thermal stability, pH tolerance and effect of inhibitors, showing optimal collagenolytic activity at 37 °C and pH 9.0 and proved to be a serine protease. ATPS showed high efficiency in the collagenase purification, confirmed by a single band in SDS/PAGE, and can in fact be applied as a quick and inexpensive alternative method.This work was supported by the National Council of Technological and Scientific Development (CNPq) and Coordination for the Improvement of Higher Education Personnel (CAPES). Sara Silvério also acknowledges her post-doc grant (SFRH/BPD/88584/2012) from FCT (SFRH/BPD/88584/2012) (Portuguese Science and Technology Foundation), Portugal

Acidocalcisomes as Calcium- and Polyphosphate-Storage Compartments during Embryogenesis of the Insect Rhodnius prolixus Stahl

BACKGROUND: The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. METHODOLOGY/PRINCIPAL FINDINGS: Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H(+)-PPase, considered as a marker for acidocalcisomes) are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.5±0.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization) and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. CONCLUSIONS: We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic events that may control embryo growth, results reveal the potential involvement of a novel organelle in the storage and mobilization of inorganic elements to the embryo cells

Cladosporium tenuissimum URM 7803: a promising new β-galactosidase producer

The Cladosporium genus, defined by Link in 1816, is one of the largest and most heterogeneous Hyphomycetes genus. It comprises more than 189 species still rarely explored biotechnologically. One of the most studied microbial enzymes, -galactosidase is a glycoside hydrolase enzyme that catalyzes the hydrolysis of -galactosides into monosaccharides through the breaking of a glycosidic bond. Recently, new studies comprising new microbial sources of -galactosidase, presenting biotechnologically interesting characteristics, have been encouraged. In this context, the present study evaluated the production of -galactosidase by a new isolate of Cladosporium tenuissimum. A C. tenuissimum inoculum was prepared adding 107 spore/mL in sterile saline solution 0.85% (w/v) NaCl containing 0.01% (w/v) Tween 80 and added to fermentation medium for enzyme production. The fermentation medium, composed of (% w/v): lactose (2), peptone (0.4), yeast extract (0.4) and salts (KH2PO4 (0.2), Na2HPO4.12H2O (0.8) and MgSO4.7H2O (0.025), pH 6.5, was maintained at 28° C and 180 rpm for 13 days. One sample (50 mL erlenmeyer) was removed every 24 hours and -galactosidase activity was evaluated using ONPG (ortho-Nitrophenyl--galactoside) method. The results showed maximum -galactosidase production by C. tenuissimum URM 7803 on thirteenth day, displayed enzymatic activity of 462.13 U/mL. The C. tenuissimum URM 7803 isolate proved to be a powerful new -galactosidase producer with potential application for food processing.info:eu-repo/semantics/publishedVersio

Plant and animal endemism in the eastern Andean slope: challenges to conservation

Andean slope: challenges to conservatio

Trophic dynamics of methylmercury and trace elements in a remote Amazonian Lake.

peer reviewedInformation on pollutant trophodynamics can be crucial for public health, as contaminated food consumption may lead to deleterious effects. This study was performed in Puruzinho Lake, a remote body of water in the Brazilian Amazon from which a riparian human population obtains an important part of its animal protein intake. Samples from 92 individuals, comprising 13 species and four trophic guilds (iliophagous, planktivorous, omnivorous, and piscivorous fish) were analysed for the determination of trace elements (Fe, Cr, Mn, Ni, Zn, Ca, Sr, Cd, Sn, Tl and Pb) and methylmercury concentrations. Samples from the same individuals had already been analysed for stable isotope (SI) measurements (δ13C and δ15N) in a previous investigation and the SI data have been statistically treated with those generated in this study for the evaluation of trophic dynamics of contaminants. Methylmercury was the only analyte that biomagnified, presenting TMF values of 4.65 and 4.55 for total and resident ichthyofauna, respectively. Trace elements presented either trophic dilution or independence from the trophic position, constituting a behaviour that was coherent with that found in the scientific literature. The similarity between Ni behaviour through the trophic web to that of essential elements contributes to the discussion on the essentiality of this metal to fish. Considering the Non-cancer Risk Assessment, the calculated Target Hazard Quotient (THQ) values were higher than 1.0 for all analysed individuals for methylmercury, as well as for only one individual for nickel. No other analyte rendered THQ values higher than 1.0.14. Life below wate

Visualizing the 3D Architecture of Multiple Erythrocytes Infected with Plasmodium at Nanoscale by Focused Ion Beam-Scanning Electron Microscopy

Different methods for three-dimensional visualization of biological structures have been developed and extensively applied by different research groups. In the field of electron microscopy, a new technique that has emerged is the use of a focused ion beam and scanning electron microscopy for 3D reconstruction at nanoscale resolution. The higher extent of volume that can be reconstructed with this instrument represent one of the main benefits of this technique, which can provide statistically relevant 3D morphometrical data. As the life cycle of Plasmodium species is a process that involves several structurally complex developmental stages that are responsible for a series of modifications in the erythrocyte surface and cytoplasm, a high number of features within the parasites and the host cells has to be sampled for the correct interpretation of their 3D organization. Here, we used FIB-SEM to visualize the 3D architecture of multiple erythrocytes infected with Plasmodium chabaudi and analyzed their morphometrical parameters in a 3D space. We analyzed and quantified alterations on the host cells, such as the variety of shapes and sizes of their membrane profiles and parasite internal structures such as a polymorphic organization of hemoglobin-filled tubules. The results show the complex 3D organization of Plasmodium and infected erythrocyte, and demonstrate the contribution of FIB-SEM for the obtainment of statistical data for an accurate interpretation of complex biological structures

Rising rural body-mass index is the main driver of the global obesity epidemic in adults

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities(.)(1,2) This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity(3-6). Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017-and more than 80% in some low- and middle-income regions-was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.Peer reviewe

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

© The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups