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To fight oxidative damage due to reactive oxygen species (ROS), cells are equipped of different enzymes, among which Peroxiredoxins (Prxs) (EC 1.11.1.15) play a key role. Prxs are thiol-based enzymes containing one (1-Cys Prx) or two (2-Cys Prx) catalytic cysteine residues. In 2-Cys Prxs the cysteine residues form a disulfide bridge following reduction of peroxide which is in turn reduced by Thioredoxin reductase (Tr) /Thioredoxin (Trx) disulfide reducing system to regenerate the enzyme. In this paper we investigated on Prxs of Thermus thermophilus whose genome contains an ORF TT_C0933 encoding a putative Prx, belonging to the subfamily of Bacterioferritin comigratory protein (Bcp): the synthetic gene was produced and expressed in E. coli and the recombinant protein, Tt Bcp, was biochemically characterized. Tt Bcp was active on both organic and inorganic peroxides and showed stability at high temperatures. To get insight into disulfide reducing system involved in the recycling of the enzyme we showed that Tt Bcp catalically eliminates hydrogen peroxide using an unusual partner, the Protein Disulfide Oxidoreductase (Tt PDO) that could replace regeneration of the enzyme. Altogether these results highlight not only a new anti-oxidative pathway but also a promising molecule for possible future biotechnological applications. [ABSTRACT FROM AUTHOR]

Abstract The reduction of energy demand and greenhouse gases (GHG) emissions is a main target of the chemical industry. By implementing Best Practice Technologies (BPTs) (i.e. the most advanced technologies currently in use at industrial scale) as well as by implementing recycling and energy recovery strategies through cogeneration and process intensification, consistent energy savings and CO 2 emissions reduction can be achieved in the short to medium term. Long-term additional cuts may arise from development and deployment of "game changer" technologies, that re-invent the way some large-volume chemicals are made. Although still far from commercial maturity and still facing high economic and technical hurdles, switching to the use of non-food biomass as fuel and feedstock in the chemical industry may represent a suitable option. During the transition towards a more energy efficient chemistry, the environmental performance of bio-based products need to be carefully evaluated on a case-by-case basis. In this study, an overview of energy improvement options is provided and the different patterns of bioethanol as fuel to generate energy or as platform chemical to generate chemical derivatives are compared as a case study within a life cycle perspective. The consequences on the environmental sustainability of the chemical industry are envisaged. Highlights • The energy efficiency implementation in the chemicals sector were investigated. • The feasibility of using non-food biomass as a "game changer" was evaluated. • Environmental impacts of bio-EtOH as fuel or as a platform chemical were assessed. • Results were discussed with regard to fossil-based and alternative bioethanol routes. [ABSTRACT FROM AUTHOR]

Abstract Pulp and paper manufacturing sector constitutes one of the largest industry segments in the world in terms of water and energy usage as well as of significant use and release of chemicals and combustion products. Since its chief feedstock –wood fiber– is renewable, this industry can play an important role in sustainable development, becoming an example of how a resource can be managed to provide a sustained supply to meet society's current and future needs. This calls for a thorough assessment of environmental costs and impacts associated to pulp and paper operations, including both direct and indirect inputs supporting the whole papermaking process as well as the main outputs, co-products and by-products. By means of Life Cycle Assessment (LCA) methodology, this paper aims at assessing the environmental sustainability of the pulp and paper production so as to identify those phases across the whole supply chain that entail the highest environmental loads, thus requiring improvements. To determine the environmental impacts as accurately as possible, the manufacturing stages performed in the pulp and paper mill complex of Stora Enso Oyj Veitsiluoto Mills at Kemi, Northern Finland, were taken as a model and assessed by means of the SimaPro 8 LCA software, utilizing ReCiPe Midpoint (H) method for the impact assessment. As expected, most of the resulting impacts are caused by the industrial production phase. The production processes of pulp and paper jointly affect all the investigated impact categories with the highest shares, ranging from 50% of generated impacts on water depletion up to 88% on freshwater eutrophication. Generally, the main contributions to environmental loads come from the electricity and heat requirements and, only at a minor extent, from the use of chemicals such as the sodium hydroxide and sodium chlorate. In particular, pulp production process generates the main loads on global warming (46% of the total impacts), ozone depletion (39%), freshwater eutrophication (55%), human toxicity (46%), metal depletion (42%) and fossil depletion (46%). In the remaining investigated impact categories, namely terrestrial acidification, photochemical oxidant formation and terrestrial ecotoxicity, most of impacts derive from the use of optical brighteners and fillers in the final steps of paper production and from the intensive consumption of water in the recycling step of end-of-life affecting water depletion. Moreover, the implementation of measures for material and energy efficiency in the assessed system, such as the use of renewable energy generated in situ from black liquor and residual biomass to support the requirements of the integrated pulp and paper mills and the waste paper recycling, resulted to be crucial in lowering the environmental burdens. In particular, the partial fulfillment of electricity and heat requirements by means of a circular use of residues within the system leads to a noteworthy reduction of impacts in all the investigated impact categories, up to more than 70% in global warming and fossil depletion potentials, thus contributing to higher process sustainability compared with other averaged European systems for paper production. The obtained research results are a valuable source of management information for the decision makers, at both company and national levels, with the aim to improve the environmental performance of pulp and paper industry. Highlights • A Life Cycle Assessment (LCA) of papermaking in Finland was performed. • The main environmental hotspots in each process step were identified and discussed. • Energy and material efficiency solutions leads to a noteworthy reduction of impacts. • Pulp and paper industry is a benchmark model to transition towards a circular economy. [ABSTRACT FROM AUTHOR]

Dtur_0462 gene from the hypertermophilic bacterium Dictyoglomus turgidum , encoding a β-glucosidase, was synthetically produced and expressed in Escherichia coli BL21(DE3)-RIL. Dtur βGlu was purified to homogeneity by affinity chromatography and its homotetrameric structure was determined by gel filtration. The monomer is composed by 418 amino acidic residues and showed high sequence similarity with Glycoside Hydrolases (GHs) belonging to GH1 family. The maximum activity of Dtur βGlu was observed at 80 °C and at pH 5.4. Dtur βGlu was stable in the range of pH 5–8 and retained 70% of its activity after 2 h of incubation at 70 °C. Metal ions and chemical reagents differently influenced the β-glucosidase activity; furthermore, Dtur βGlu displays a good ethanol and glucose tolerance (K i 750 mM). The enzyme is active on p -nitrophenyl-β- d -glucopyranoside ( p NPGlu) (K m 0.84 mM) and p -nitrophenyl-β- d -galactopyranoside ( p NPGal) (K m 1.36 mM) and shows a broad substrate specificity towards natural compounds as salicin, cellobiose and genistin. The ability to hydrolyze different substrates, the activation in the presence of surfactants, the good thermal resistance, and finally the high glucose and ethanol tolerance make this enzyme a good candidate for industrial applications. [ABSTRACT FROM AUTHOR]

Abstract: Successful market penetration of Fuel Cell (FC) technologies requires increased research and technological efforts towards improved efficiency, durability, costs and environmental performance according to accepted standards. Life Cycle Assessment (LCA) can help understand to what extent FCs are environmentally sound, to what extent they can be improved and what steps and components require attention. A guidance manual for LCA application to FC technologies, processes and systems, compliant with the International Reference Life Cycle Data System (ILCD), was developed within the European Union-funded Fuel Cell-Hydrogen Guide (FC-Hy Guide) Consortium. The purpose was to provide entrepreneurs, consultants and experts with a specific guidance tool for use in policy context and decision-making. This paper presents the application of the FC-Hy Guide scheme to Molten Carbonate Fuel Cells (MCFC), with focus on the following aspects: (1) data quality; (2) information needed; (3) background and foreground data; (4) FC stack and balance of system; (5) improvement potential; (6) sensitivity of results and data uncertainty. [Copyright &y& Elsevier]

Abstract: A selective removal of humic constituents involved in ester groups was conducted by a boron trifluoride–methanol transesterification reaction after removal of structurally unbound lipids. An analytical separation of subfractions containing specific classes of compound liberated from the humic matrix simplifies their identification by gas chromatography–mass spectrometry. We compared the traditional liquid–liquid separation into phenolic and aliphatic fractions with the modern and versatile fractionation technique using solid-phase extraction (SPE) on aminopropyl-bonded phases. Our results showed that both methods ensured separation of the same compounds, such as di- and tri-hydroxyalkanoic acids, α-, β- and ω-hydroxy fatty acids, alkanoic acids, α,ω-alkanedioic acids, n-alkanols, phenolic acids and sterols. Moreover, the SPE method not only provided a larger recovery of compounds, but involved smaller sample and solvent requirements, and larger ease and rapidity of sample handling than the traditional liquid–liquid separation. The SPE method should be thus recommended in structural studies of natural organic matter. [Copyright &y& Elsevier]

The linear path "extraction-production-consumption-waste", imposed by humans to natural ecosystems, where all material flows are instead circular, has become unsustainable. Understanding the potential value of some of these "by-products", in order to exploit them effectively in a biorefinery perspective, may help overcoming resource shortages and decrease environmental impacts. This study investigates energy and resource restoration from animal by-products. The slaughterhouse waste undergoes a rendering process to separate residual meal and fat. The latter is combusted in a co-generation plant to produce electricity and heat. The process is carefully assessed using Emergy Accounting approach with the aim of evaluating benefits and environmental load of the process considering the advantages achieved compared with the demand for ecosystem services and natural capital depletion. Moreover, the case aims at exploring three different methodological assumptions referring to the upstream burdens carried by the waste management system, proposing a modified exergy-based allocation rule. The electricity generated shows performances in terms of Unit Emergy Values ranging between 2.7E+05 sej/J, 2.2E+06 sej/J and 3.1E+07 sej/J among the different cases investigated, comparable to power from fossil fuels and renewables sources, and it provides an environmentally sound alternative to conventional waste disposal. • Linear "take-make-dispose" patterns in food production are environmentally unsustainable. • Circular strategies improve the environmental and economic performances of food chain. • Electricity generation out of slaughterhouse waste is suggested as a circular alternative to landfilling. • A modified emergy approach is applied for the evaluation of resource and waste intensive processes. • The emergy approach allows a comprehensive sustainability understanding to integrate monetary and LCA evaluations. [ABSTRACT FROM AUTHOR]

The full utilization of hemicellulose sugars (pentose and exose) present in lignocellulosic material, is required for an efficient bio-based fuels and chemicals production. Two recombinant thermophilic enzymes, an endo -1,4-β-mannanase from Dictyoglomus turgidum ( Dtur CelB) and an α-galactosidase from Thermus thermophilus ( Tt GalA), were assayed at 80 °C, to assess their heterosynergystic association on galactomannans degradation, particularly abundant in hemicellulose. The enzymes were tested under various combinations simultaneously and sequentially, in order to estimate the optimal conditions for the release of reducing sugars. The results showed that the most efficient degree of synergy was obtained in simultaneous assay with a protein ratio of 25% of Dtur CelB and 75% of Tt GalA, using Locust bean gum as substrate. On the other hand, the mechanism of action was demonstrated through the sequential assays, i.e. when Tt GalA acting as first to enhance the subsequent hydrolysis performed by Dtur CelB. The synergistic association between the thermophilic enzymes herein described has an high potential application to pre-hydrolyse the lignocellulosic biomasses right after the pretreatment, prior to the conventional saccharification step. [ABSTRACT FROM AUTHOR]

As China's photovoltaic (PV) sector experiences rapid growth, the availability of land resources has become a pivotal policy focus, driving the need for comprehensive research and strategic planning for roadside PV initiatives. Utilizing a fuzzy multi-criteria decision-making approach, combined with GIS spatial analysis and a modular design framework, our study quantitatively compared the carbon reduction capabilities of PV systems against the carbon sequestration potential of various vegetative arrangements along the roadside space. The roadside space analysis modular considers a range of factors including topography, meteorology, and construction costs. We examined the spatial distribution of suitability for PV installation and vegetation establishment along the provincial expressway network in China. The results revealed that Inner Mongolia stood out as the frontrunner in carbon reduction potential within high-suitability zones for PV construction, achieving an impressive 4.845 million tons of carbon reduction—nearly four times greater than that of Shaanxi Province. In contrast, the carbon sequestration attributed to vegetation greening in areas less suited for PV development revealed a higher propensity in the southeastern provinces. Guangdong led the charge with an impressive annual carbon sequestration of 2.89 million tons. This was closely followed by Yunnan, Sichuan, Hebei, Guizhou, and Henan, each achieving carbon sequestration amounts exceeding 2 million tons. These results offer valuable quantitative support and practical recommendations for achieving low-carbon objectives in the construction of China's expressways. • Develop a multi-criteria decision-making framework. • Photovoltaic construction has great carbon reduction potential. • Modular design calculates vegetation's carbon sequestration. • The insights offer valuable quantitative support to advance low-carbon expressway construction objectives. [ABSTRACT FROM AUTHOR]

• The study promotes a standardized framework for the analysis of complex systems. • Life Cycle Assessment (LCA) and Emergy Accounting (EMA) are integrated for synergy. • Differences and similarities between LCA and EMA add value for deeper understanding. • The proposed framework is based on ex-ante LCA, EMA and ex-post LCA procedures. The analysis of complex systems requires an integrated application of different assessment methods also taking into account different scales and points of view to gain a systemic understanding of the investigated case study. Life Cycle Assessment (LCA) and Emergy Accounting (EMA) are both environmental assessment methods, showing many similarities in the way they are performed, especially with respect to the inventory construction and to the interpretation of results. They also show great differences, the main residing in the different perspectives they give. LCA applies a consumer side perspective, and its space and time scales are set at a boundary capable to include all the process phases in terms of location and durability and their direct impacts on the investigated areas. On the other hand, throughout its donor side perspective, EMA expands the boundaries of the system over the entire biosphere space and time scales. Differences and similarities between LCA and EMA may gain added value by their implementation within a procedural framework which exploits the characteristics of the two methods. The present work proposes a methodological procedure based on the sequential and integrated application of LCA and EMA methods, called LEAF (LCA & EMA Applied Framework). The traditional Amalfi paper production is used as a test case study. The procedure stems include: (i) an ex-ante LCA analysis, to identify the hotspots of the investigated case study; (ii) the assessment of the environmental performance of the system through the development of different EMA-based improvement scenarios built around the chosen hotspots; and (iii) an ex-post LCA application built on each scenario results in order to detect the different environmental burdens. The application of LEAF to the traditional Amalfi paper production shows that the use of a more sustainable energy source is an effective solution (among the set of proposed options) to increase the sustainability of the investigated system. [ABSTRACT FROM AUTHOR]

Saliva of blood-feeding arthropods carries several antihemostatic compounds whose physiological role is to facilitate successful acquisition of blood. The identification of novel natural anticoagulants and the understanding of their mechanism of action may offer opportunities for designing new antithrombotics disrupting blood clotting. We report here an in-depth structural and functional analysis of the anophelin family member cE5, a salivary protein from the major African malaria vector Anopheles gambiae that specifically, tightly, and quickly binds and inhibits thrombin. Using calorimetry, functional assays, and complementary structural techniques, we show that the central region of the protein, encompassing amino acids Asp-31-Arg-62, is the region mainly responsible for α-thrombin binding and inhibition. As previously reported for the Anopheles albimanus orthologue anophelin, cE5 binds both thrombin exosite I with segment Glu-35-Asp-47 and the catalytic site with the region Pro-49-Arg-56, which includes the highly conservedDPGRtetrapeptide. Moreover, the N-terminal Ala-1-Ser-30 region of cE5 (which includes an RGD tripeptide) and the additional C-terminal serine-rich Asn-63-Glu-82 region (absent in orthologues from anophelines of the New World species A. albimanus and Anopheles darlingi) also played some functionally relevant role. Indeed, we observed decreased thrombin binding and inhibitory properties even when using the central cE5 fragment (Asp-31-Arg-62) alone. In summary, these results shed additional light on the mechanism of thrombin binding and inhibition by this family of salivary anticoagulants from anopheline mosquitoes. [ABSTRACT FROM AUTHOR]

Evaluation of vector control is crucial for improving malaria containment and, according to World Health Organization, new complementary indicators would be very valuable. In this study the IgG response to the Anopheles -specific cE5 salivary protein was tested as a tool to evaluate the efficacy of insecticide-treated nets in reducing human exposure to malaria vectors. Sera collected during a longitudinal study carried out in Angola, and including entomological and parasitological data, were used to assess the IgG response to the Anopheles gambiae cE5 in both children and adults, before and after the application of insecticide-treated nets. Seasonal fluctuation of specific IgG antibody levels according to exposure was only found in children (up to ≈14 years old) whose anti-cE5 IgG response dropped after bed nets installation. These results were fully consistent with previous findings obtained with the same set of sera and indicating a substantial reduction of human-vector contact shortly after nets implementation. Overall, children IgG response to the cE5 protein appeared a very sensitive biomarker, which allowed for the detection of even weak exposure to Anopheles bites, indicating it may represent a reliable additional tool to evaluate the efficacy of vector control interventions. [ABSTRACT FROM AUTHOR]

Abstract: Mosquito saliva carries a large number of factors with anti-hemostatic, anti-inflammatory and immuno-modulatory activities. The cE5 protein was initially identified during an Anopheles gambiae salivary gland transcriptome study and later shown to share sequence similarity with anophelin, a thrombin inhibitor from the saliva of the New World mosquito Anopheles albimanus. The cE5 gene was found to encode different mRNA isoforms coexisting in several tissues of both male and female mosquitoes, a highly unusual profile for a gene potentially encoding an anti-thrombin and involved in blood feeding. Expression of the cE5 protein and assessment of its activity and inhibitory properties showed that it is a highly specific and tight-binding thrombin inhibitor, which differs from the A. albimanus orthologue for the fast-binding kinetics. Despite the widespread occurrence of cE5 transcripts in different mosquito tissues the corresponding protein was only found in female salivary glands, where it undergoes post-translational modification. Therefore, tissue-specific restriction of the A. gambiae cE5 is not achieved by transcriptional control, as common for mosquito salivary genes involved in hematophagy, but by post-trascriptional gene regulatory mechanisms. Our observations provide a paradigm of post-transcriptional regulation as key determinant of tissue specificity for a protein from an important disease vector and point out that transcriptomic data should be interpreted with caution in the absence of concomitant proteomic support. [Copyright &y& Elsevier]

Abstract: The Anopheles gambiae salivary gland protein 6 (gSG6) is a small protein specifically found in the salivary glands of adult female mosquitoes. We report here the expression of a recombinant form of the protein and we show that in vivo gSG6 is expressed in distal-lateral lobes and is secreted with the saliva while the female mosquito probes for feeding. Injection of gSG6 dsRNA into adult A. gambiae females results in decreased gSG6 protein levels, increased probing time and reduced blood feeding ability. gSG6 orthologs have been found so far only in the salivary glands of Anopheles stephensi and Anopheles funestus, both members of the Cellia subgenus. We report here the gSG6 sequence from five additional anophelines, four species of the A. gambiae complex and Anopheles freeborni, a member of the subgenus Anopheles. We conclude that gSG6 plays some essential blood feeding role and was recruited in the anopheline subfamily most probably after the separation of the lineage which gave origin to Cellia and Anopheles subgenera. [Copyright &y& Elsevier]