Over the last few decades, researchers have been intrigued by the fascinating polyextremophiles microrganisms that inhabit extreme environments. Such organisms are being looked upon as stars for industrial biotechnology that function under acute conditions in which usually the enzymes of their non-extremophilic counterparts could not. The application of hydrolases in industrial processes sometimes fails due to the lack of robustness, stability and undesirable properties. Thanks to their biochemical properties, they are relevant for specific industrial applications that determine the demand for tailor-made enzymes and shift the industrial interest towards biocatalysts from extremophiles including proteases. A new extracellular thermostable serine alkaline protease (designated SAPA) was produced, purified, and characterized from Anoxybacillus kamchatkensis M1V. The bacterial strain was found to hyper-produce extracellular protease when grown at 45 °C in optimized media (4,600 U/mL). The purification to homogeneity of the SAPA enzyme was achieved, simultaneously, by precipitation with ammonium sulfate fractionation-dialysis, anion exchange (FPLC), and gel filtration (HPLC) chromatographies. It had a relative molecular mass of 28 kDa as estimated by SDS-PAGE. The sequence of its NH₂-terminal amino-acid residues showed high homology with those of Bacillus proteases. It showed optimal activity at pH 11 and 70 °C. The thermoactivity and thermostability of SAPA were enhanced in the presence of 2 mM Ca²⁺. Irreversible inhibition of the enzyme activity by DFP and PMSF confirmed its belonging to the serine proteases family. Interestingly, SAPA displayed higher levels of hydrolysis, substrate specificity, and catalytic efficiency than proteases viz. SPVP from Aeribacillus pallidus strain VP3, SAPB from Bacillus pumilus strain CBS, Subtilisin A from B. licheniformis, and Subtilisin 309 from B. clausii. More interestingly, SAPA showed a high detergent stability and compatibility and an outstanding stain removal compared to commercial enzymes viz. Alcalase™ and Savinase™. The sapA gene was cloned, sequenced, and expressed in the extracellular fraction of E. coli strain BL21(DE3)pLysS. The biochemical properties of the extracellular purified recombinant enzyme (rSAPA) were similar to those of native SAPA. The deduced amino-acid sequence showed strong homology with other Bacillus proteases. The highest sequence identity value (95%) of SAPA was obtained with peptidase S8 from B. subtilis, with 16 amino-acids of difference. Above all, SAPA exhibited remarkable biochemical proprieties which may be considered as a potential candidate for biotechnological applications such as a cleaning bio-additive in laundry detergent formulations.

Background and aim: The use of enzymes in the textile industry is an example of white/industrial biotechnology, which allows the development of environmentally friendly technologies in fibre processing and strategies to improve the final product quality. The consumption of energy and raw-materials, as well as increased awareness of environmental concerns related to the use and disposal of chemicals into landfills, water or release into the air during chemical processing of textiles are the principal reasons for the application of enzymes in finishing of textile materials. Owing to the quality of the workforce, political stability, economic, and geographical approximation with Europe, textile sector has a significant importance in the Tunisian economy. The aim of this study is to isolate a new fungi protease, with excellent proprieties in order to be used as a bio-additive in detergent formulation with any destructive effect on textile supports.

Methods: The ITS rDNA gene-sequencing was used to identify the fungus strain X5. The biochemical and chemical characterization of the pure enzyme were investigated though physico-chemical and kinetic determination as well as spectroscopy analysis.

Results: A new extracellular thermostable serine alkaline protease (SAPTEX) was purified to homogeneity and biochemically characterized from P. chrysogenium X5 as a monomer with 43 kDa. The experimental purification protocol comprises three steps: heat treatment followed by an ammonium sulfate precipitation, and a FPLC/UNO Q-12 anion exchange chromatography. The optimum pH and temperature values for protease activity were pH 10 and 80°C, respectively. Compared to other proteases (SPTC; Flavourzyme® 500L; Proteinase, type XXIII; Proteinase K; and Alcalase® 2.4L), SAPTEX has the highest catalytic efficacy, hydrolysis degree, and a powerful stability toward some commercial detergents. According to morphological, physico-chemical, and metrological evaluation, SAPTEX has no destructive impact on fibers after the enzyme treatment and a very slight effect on textile support. Data suggested that SAPTEX may be considered a potential candidate as a protein stain removal product from textile supports.

Conclusion: Overall, the findings indicate that SAPTEX is bestowed with a number of promising properties that may be considered as potential candidate for protein stain removal from textile supports in the textile processing applications.

The definition of more realistic scenarios of instances for the portfolio selection problems (PSP) of new product developments usually should involve precedence relations that generate effects related to time-interdependence among different projects. The study of time -interdependences, or time effects, on the selection of projects captures our attention because they affect the problem objective functions. Three different moments have been identified as usually present in any project: 1) the estimated completion time; 2) the moment in which the competence become significant; and, 3) the moment in which the developed product becomes old. A PSP under such temporal constraints (denoted PSPTC) could face risk because the lack of reliable data derived from long lead times of projects, or by a complex market and technology dynamics; such imperfect knowledge could cause variability in the benefits and requirements of a PSPTC. In this sense, this paper proposes the design of an optimization model for PSPTC under uncertainty, and the study of their influence in choosing optimal project portfolios of new product developments. This work proposes an interval-based approach to deal with PSPTC; this approach has the advantage of a unified and simple way to model the different sources of imprecision, uncertainty and arbitrariness. Also, the model is parametrized such that the attitude of the DM facing the imperfect knowledge can be adjusted by using two meaningful parameters.

References

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5. Ke, H., & Liu, B. (2007). Project scheduling problem with mixed uncertainty of randomness and fuzziness. European Journal of Operational Research, 183 (1), 135-147. http://doi.org/10.1016/j.ejor.2006.09.055.

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The Water Framework Directive 2000/60/EC regulates the environmental diagnosis of the marine ecosystem, including the evaluation of species of bioindicator macroinvertebrates present in the environment. To date, these types of determinations are carried out through the morphotaxonomic identification of the benthic macrofauna present in the samples and the calculation of associated biotic indexes, a process that is time-consuming and resource-intensive, being in some cases inaccurate due to the requirement of highly specialized human resources and the difficulty of correctly identifying certain species. In this respect, DNA barcoding techniques allow the reliable identification of organisms using DNA sequencing techniques and avoiding the disadvantages of morphotaxonomic identification. On the other hand, the recent development of New Generation DNA Sequencing techniques (NGS) has allowed the development of DNA metabarcoding, i.e. the characterization of populations of organisms present in a sample using genomic data. This paper shows the fundamental challenges to be overcome in order to establish a NGS sequencing-based assessment of the marine environmental quality.

Nowadays enterprises face the necessity of taking many decisions related to their everyday activities. Usually, these decisions are made over real world problems whose solutions contribute to the achievement of desire results. The most common strategy followed to provide assistance in such situations is through the development of optimizations models that reflects the needs of an enterprise but also that incorporates particular preferences of the Decision Maker (DM) who is meant to select the best solution.

According to the revised literature, the strategies that have been used so far to model preferences are based on goal attainment, utility functions, preference relations, outranking and fuzzy logic. Of particular interest are the outranking approaches which exploits outranking relations to give answer to Multi-objective Optimization Problems (MOPs); such approach has allowed the development of computable preference models, based on a predefined set of parameters, that reflect the interests of a DM. The most practical way that can be used to set the parameter values for that preference model is through Preference Disaggregation Methods (PDM), which are methods that based on a battery of examples provided by the DM elicits the entire set of parameters.

Recently it has been observed that the preferences of a DM are strongly influenced by abstract aspects of his/her personality, e.g. his/her level of tolerance. In this direction, the personality and the emotional state are relevant elements that provide in some way an added value to these preferences, and they could produce more descriptive and approximate solutions to the reasoning of the individual. Hence, it is acceptable to think that the personality should influence the values of the parameters that define a specific preference model that is used to characterize a DM.

This work analyzes the effects of personality over parameter values of preference models. It presents an architecture that takes as input aspects of a personality and use them to modify the parameter values of a preference model. The elements considered were ELECTRE III, a well-known model that takes into account the preferences of a DM, a proposed personality model which uses the most recurrent models of the theory of personality theory to provide a computable measure of the tolerance of an individual, and a proposed methodology to modify the parameters of ELECTRE III due to the personality. In this cognitive process, it was possible to identify the parameters where the personality can influence preferences.

The case study presented in this research is a basic case of purchases in an online super market, where a virtual assistant interacts with the decision maker emulating their behavior when selecting products based on their preferences and personality, in order to facilitate the decision maker chooses the most convenient solution.

The main objective in the proposed research is the study of the impact of the influence of personality on preferences within a decisional context. To prove the above, an experimental design is proposed, it simulates series of purchases based on lists of initial product requests to determine whether the purchases of the resulting products are close to the products originally requested.

Proteases represents one of the major groups of industrial enzymes and a number of detergent stable proteases have been isolated and characterized because of its widespread use in detergents. It is worthwhile to screen microbes from new habitats for proteases with novel properties to meet the needs of rapidly growing detergent industry. High-alkaline serine proteases have been successfully applied as protein degrading components of detergent formulations and are subject to extensive protein engineering efforts to improve their stability and performance. Protein engineering has been extremely used to study the structure-function relationship in proteases and led to deeper understanding of the factors influencing the cleaning performance of detergent proteases. The aim of this work is to produce an alkaline protease having characteristics allowing its potential incorporation and application in the detergence industry. Enzyme purification was conducted using the sulfate ammonium precipitation. The amplifications of the ARNr 16S and the gene encoding for the studied protease were performed by PCR. A collection of 88 strains was subjected to the screening of proteolytic activity in solid medium. Thirty-six strains showed a halo of inhibition which correspond to the protease activity. The strain F-35, isolated from wastewater at the EJM Company, which exhibited the largest halo of inhibition, was retained for further studies and assigned as Bacillus velezensis based on physiological and biochemical properties and 16S rRNA gene sequencing. The study of the effect source of carbon and azote on the activity of the studied protease showed that the best activity of 7500 U/ml was obtained by combining the Modilac (powdered milk) and the yeast extract. The characterization of the physico-chemical properties showed that the partial protease has an optimum activity at 60 °C and pH 10. The partial enzyme exhibited excellent stability and compatibility with surfactants and commercial detergents, revealing 95% stability with 2% LAS and 100% stability with Class and Arial commercial laundry detergents. The gene encoding for the studied protease was amplified by PCR and showed a size of 1.5 kb. Accordingly, such a protease could be considered as a good detergent-additive in detergent industry.

A number of newly isolated halophilic microorganisms were screened for protease production. A bacterium designated as strain SBJ9 showed an important enzyme production at high salt concentrations and was then retained. The 16S DNA identification put this strain in the genus of Salicola with two reference species only. Protease production was higher at salinities ranging from 150 to 200 g/l (3.2 M) NaCl, when monitored at 35 °C and pH 7. The protease activity was optimal at 2.5 MNaCl, 40°C and pH 8, with high stability at wide ranges of salinity (1-5 MNaCl), temperatures (20- 70 °C) and pH values (5- 11). It was slightly improved by 5 mM CaCl₂ and totally inhibited by PMSF which indicated the dominance of serine proteases. Besides, it was perfectly stable in the presence of many detergent additives and organic solvents at high concentrations. These important features make Salicola sp. strain SBJ9 protease activity a good candidate for many industrial applications such as detergency and organic synthesis.

Enzymes are fascinating the researchers because of their enormous power of catalysis and eco-friendly nature. In biotechnological processes, diversity of microbes is studied, and different metabolic reactions entitle a potential repository that direct valuable production of desirable products. Although tremendous scientific and technological advances have been made by researchers and industrial enzyme producers, and despite the large flow of data on bacterial proteases, little data is currently available on the purification and characterization of proteases and keratinases from B. safensis. Accordingly, the present study reports on the purification and biochemical characterization of a novel detergent-stable protease (SAPRH) from B. safensis strain RH12 isolated from offshore sediment in the Gulf of Gabes (Tunisia). A novel extracellular protease (SAPRH) was hyper-produced (9,000 U/mL) from Bacillus safensis RH12. The enzyme was purified to homogeneity using salt-precipitation, heat-treatment, and FPLC anion-exchange chromatography. The purified enzyme is a monomer of molecular mass of ~28 kDa. The NH₂-terminal 23 amino-acid sequence of SAPRH showed high homology with those of Bacillus-proteases. SAPRH showed optimal activity at pH 9 and 60°C. It is strongly inhibited by PMSF and DFP, showing that it belongs to the serine-proteases family. Moreover, SAPRH was extremely stable at a broad range of temperature and pH retaining 85% of its activity at 50°C and 75% at pH 11. The enzyme exhibited excellent-stability and compatibility with surfactants and commercial detergents, showing 90% stability with SDS and 100% stability with Class commercial laundry detergent. One of the distinguishing properties is its catalytic efficiency, which is higher than that of Alcalase 2.5 L, type DX (commercial enzyme) and SAPB from B. pumilus strain CBS. Interestingly, the results of the wash performance analysis demonstrated considerably good de-staining at 40°C for 30 min with low supplementation (500 U/mL). Accordingly, such protease can be considered as a good detergent-additive in detergent industry.

Salicola sp. strain SBJ9 is an extremely halophilic bacterium newly isolated from a hypersaline lake in Sfax (Tunisia). It is an aerobic Gram negative bacterium, bacilli shaped and motile. The strain SBJ9 grows optimally at 150 g/l (2.57 M) NaCl, 35 °C and pH 7 and it is able to hydrolyze proteins and lipids at high salinities. Actually, Salicola genus contains only two species (S. marasensis and S. salis). This research reported the first draft genome of a bacterium belonging to Salicola and the different obtained and annotated sequences and genes. Salicola sp. strain SBJ9 genomic sequence contains 4.643.441 bp with a G+C content of 60.52%. The annotation monitored by the RAST server reveals 65 RNA sequences and 3995 coding genes including 255 and 182 sub-systems of protein metabolism and lipids, respectively. The further analysis of SBJ9 genomic sequence will clarify the ideas regarding the adaptation of the Salicola strains and their proteins to the extremely high salt concentrations and will permit the development of new bio-catalyzers for industrial applications.

A Fusion Transcript (FT) is a RNA molecule product of cis/trans-splicing of two differently annotated elements, either genes or Transposable Elements (TE). It may be coding or non-coding. There are many examples of gene-gene FTs in cancer. Lately, FTs have been also reported in control conditions in different organisms. Moreover, other authors argue that a FT might be a product of artifacts, either experimental or computational. In a recent work, we have developed a pipeline to predict FTs between an exon and a TE. In it, we have found 813 exon-TE FTs from 438 different genes. This prediction was made starting with RNA-seq data from Nucleus Accumbens in mouse (M. musculus) treated with cocaine vs. control. From that group, 20 candidates were taken and all were validated experimentally through PCR. However, the depth of sequencing is low. We can further gather supporting evidence of their expression by filtering the candidates, which could be regulated by small RNAs, the same way piRNAs regulate TEs. We aligned around 5 million mouse piRNAs against the 813 mouse exon-TE Fts, identifying 112 piRNAs that map only across the juction point of exon-TE FTs, in 56 genes. These piRNAs do not map on the reference genome or on the transcriptome sequences. These results suggest that either: 1) piRNAs might regulate the expression of exon-TE FTs, or 2) the exon-TE Fts may be the origin of piRNAs. In either case, they suggest that exon-TE FTs may express in germline. Grant Fondecyt #11140869.