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2017
Carrera, GVSM, Raymundo A, Fernandes FMB, Jordao N, Sousa I, da Ponte MN, Branco LC.  2017.  Tetramethylguanidine-based gels and colloids of cellulose, 2017. Carbohydrate Polymers. 169:58-64. AbstractWebsite
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Beira, MJ, Daniel CI, Almeida PL, Corvo MC, Rosatella AA, Afonso CAM, Sebastiao PJ.  2017.  1H NMR Relaxometry and Diffusometry Study of Magnetic and Non-Magnetic Ionic Liquid-Based Solutions: Co-Solvent and Temperature Effects. The Journal of Physical Chemistry B. : ACS Publications AbstractWebsite

In this work, 1H NMR relaxometry and diffusometry as well as viscometry experiments were carried out as a means to study the molecular dynamics of magnetic and non-magnetic ionic liquid-based systems. In order to evaluate the effect of a co-solvent on the super-paramagnetic properties observed for Aliquat-iron-based magnetic ionic liquids, mixtures comprising different concentrations, 1% and 10% (v/v), of DMSO-d6 were prepared and analyzed. The results suggest that, when at low concentrations, DMSO-d6 promotes more structured ionic arrangements, thus enhancing these super-paramagnetic properties. Furthermore, the analysis of temperature and water concentration effects allowed to conclude that neither one of these variables sufficiently affected the super-paramagnetic properties of the studied magnetic ionic liquids.

Marques, AC, Santos L, Dantas JM, Gonçalves A, Casaleiro S, Martins R, Salgueiro CA, Fortunato E.  2017.  Advances in electrochemically active bacteria: Physiology and ecology. Handbook of Online and Near-real-time Methods in Microbiology. : CRC Press Abstract

The discovery of microorganisms with the ability of Extracellular Electron Transfer (EET), nearly three decades ago, sparked interest due to their ability to be used in diverse applications that can range from bioremediation to electricity production in Microbial Fuel Cells (MFC). Microbial respiration is based on electron transfer from a donor to an electron acceptor, through a series of stepwise electron transfer events that generate the necessary metabolic energy. Some microorganisms, such as Pseudomonas species, Shewanella putrefaciens or Geothrix fermentans are able to produce electrochemical mediators to increase the EET. The mechanical stability of the biofilm is provided by the biofilm matrix, a hydrated extracellular polymeric matrix that encases the biofilm cells. The biofilm matrix could potentially offer a resistance pathway to EET unless bacteria develop strategies to increase its conductivity. MFC devices currently being used and studied do not generate sufficient power to support widespread and cost-effective applications.

Dupont, J, Simon NM, Zanatta M, dos Santos FP, Corvo MC, Cabrita EJ.  2017.  Carbon dioxide capture by aqueous ionic liquid solutions. ChemSusChem. AbstractWebsite

Confined water in aqueous solutions of imidazolium-based ionic liquids (ILs) associated with acetate and imidazolate anions react reversibly with CO2 to yield bicarbonate. Three types of CO2 sorption in these “IL aqueous solutions” were observed: physical, CO2-imidazolium adduct generation, and bicarbonate formation (up to 1.9 molbicarbonate mol−1 of IL), resulting in a 10:1 (molar ratio) total absorption of CO2 relative to imidazolate anions in the presence of water 1:1000 (IL/water). These sorption values are higher than the classical alkanol amines or even alkaline aqueous solutions under similar experimental conditions.

Carreira, C, Pauleta SR, Moura I.  2017.  The catalytic cycle of nitrous oxide reductase - The enzyme that catalyzes the last step of denitrification. J Inorg Biochem. 177:423-434.
Berride, F, Troche-Pesqueira E, Feio G, Cabrita EJ, Sierra T, Navarro-Vázquez A, Cid MM.  2017.  Chiral amplification of disodium cromoglycate chromonics induced by a codeine derivative. Soft Matter. 13(38):6810-6815. AbstractWebsite

Chromonic liquid crystals (CLC) are lyotropic phases formed by discotic mesogens in water. Simple chiral dopants such as amino acids have been reported to turn chromonic liquid crystals into their cholesteric counterparts. Here we report a chirality amplification effect in the nematic phase of a 9 wt% disodium cromoglycate (DSCG) lyotropic liquid crystal (LLC) upon doping with a water-soluble codeine derivative. The transition on cooling the isotropic to the nematic phase showed the presence of homochiral spindle-shaped droplets (tactoids). NMR DOSY experiments on a triple gradient probe revealed a small degree of diffusion anisotropy for the alkaloid embedded in the liquid crystal structure. These results in combination with XRD, CD and POM experiments agree with a supramolecular aggregation model based on simple columnar stacks.

Matias, SC, Lourenço NMT, Fonseca JP, Cordas CM.  2017.  Comparative electrochemical behavior of cytochrome c on aqueous solutions containing choline-based room temperature ionic liquids. ChemistrySelect. 2:8701–8705.Website
Cruz, H, Jordão N, Amorim P, Dionísio M, Branco LC.  2017.  Deep Eutectic Solvents as Suitable Electrolytes for Electrochromic Devices. ACS Sustainable Chemistry and Engineering. 6(2):2240-2249.Website
Ribeiro, SO, Nogueira LS, Gago S, Almeida PL, Corvo MC, de Castro B, Granadeiro CM, Balula SS.  2017.  Desulfurization Process conciliating Heterogeneous Oxidation and liquid extraction: Organic Solvent or Centrifugation/Water? Applied Catalysis A: General. : Elsevier AbstractWebsite

The present work presents a strategic oxidative desulfurization system able to efficiently operate under sustainable conditions, i.e. using an eco-friendly oxidant and without the need of extractive organic solvents. The catalytic performance of Eu(PW11O39)2@aptesSBA-15 was evaluated for the oxidative desulfurization of a multicomponent model diesel using a solvent-free or biphasic systems. The results reveal its remarkable desulfurization performance achieving complete desulfurization after just 2 h of reaction. Moreover, the composite has shown a high recycling ability without loss of catalytic activity for ten consecutive ODS cycles. Interestingly, under solvent-free conditions it was possible to maintain the desulfurization efficiency of the biphasic system while being able to avoid the use of harmful organic solvents. In this case, a successful extraction of oxidized sulfur compounds was found conciliating centrifugation and water as extraction solvent. Therefore, this work reports an important step towards the development of novel eco-sustainable desulfurization systems with high industrial interest.

Peixoto, D, Figueiredo M, Gawande MB, Corvo MC, Vanhoenacker G, Afonso CAM, Ferreira LM, Branco PS.  2017.  DEVELOPMENTS IN THE REACTIVITY OF 2-METHYL IMIDAZOLIUM SALTS. The Journal of Organic Chemistry. 82(12):6232–6241.: American Chemical Society AbstractWebsite

Unexpected and unusual reactivity of 2-methylimidazolium salts toward aryl-N-sulfonylimines and aryl aldehydes is here reported. Upon reaction with aryl-N-sulfonylimines, the addition product, arylethyl-2-imidazolium-1-tosylamide (3), is formed with moderate to good yields, while upon reaction with aldehydes, the initial addition product (6) observed in NMR and HPLC–MS experimental analysis is postulated by us as an intermediate to the final conversion to carboxylic acids. Studies in the presence and absence of molecular oxygen allow us to conclude that the imidazolium salts is crucial for the oxidation. A detailed mechanistic study was carried out to provide insights regarding this unexpected reactivity.

Machado, C, Carvalho F, Costa M, Martins S, Machado A, Ruivo A, Lima A, Ferreira JL, Vilarigues M.  2017.  History of materials: a new tool for conservation of glass and ceramics; Education and Research in Conservation – Restoration. ENCoRE 2016. , Cambridge
Dajkovic, A, Tesson B, Chauhan S, Courtin P, Keary R, Flores P, Marliere C, Filipe SR, Chapot-Chartier M-P, Carballido-Lopez R.  2017.  Hydrolysis of Peptidoglycan is Modulated by Amidation of meso-Diaminopimelic Acid and Mg2+ in Bacillus subtilis. Mol. Microbiol. 104:972-988.
Pauleta, SR, Carreira C, Moura I.  2017.  Insights into nitrous oxide reductase. Metalloenzymes in Denitrification: Applications and Environmental Impacts, RSC Metallobiology Series No. 9 (ISBN: 978-1-78262-376-2).. (Moura, I., Moura, J. J. G., Pauleta, S. R., Maia, L. B., Eds.).:141-169.: Royal Society of Chemistry
Ramos, S, Almeida RM, Cordas CM, Moura JJG, Pauleta SR, Moura I.  2017.  Insights into the recognition and electron transfer steps in nitric oxide reductase from Marinobacter hydrocarbonoclasticus. J Inorg Biochem. 177:402-411.
Gargiulo, M, Chiodi A, De Miglio R, Simoes S, Long G, Pollard M, Gouveia JP, Giannakidis G.  2017.  An Integrated Planning Framework for the Development of Sustainable and Resilient Cities - The Case of the InSMART Project. Procedia Engineering. 198:444-453.
Carvalho, HF, Barbosa A, Roque ACA, Iranzo O, Branco RJF.  2017.  Integration of Molecular Dynamics Based Predictions into the Optimization of de novo Protein Designs: Limitations and Benefits. Computation Protein Design. :181-201.
Costa, E, Seixas J, Costa G, Turrentine T.  2017.  Interplay between ethanol and electric vehicles as low carbon mobility options for passengers in the municipality of São Paulo. JOURNAL OF SUSTAINABLE TRANSPORTATION. 7(11):518-525.
Bonnet, A, Grosso AR, Elkaoutari A, Coleno E, Presle A, Sridhara SC, Janbon G, Geli V, de Almeida SF, Palancade B.  2017.  Introns Protect Eukaryotic Genomes from Transcription-Associated Genetic Instability. Molecular Cell. :1–14. AbstractWebsite

Transcription is a source of genetic instability that can notably result from the formation of genotoxic DNA:RNA hybrids, or R-loops, between the nascent mRNA and its template. Here we report an unexpected function for introns in counteracting R-loop accumulation in eukaryotic genomes. Deletion of endogenous introns increases R-loop formation, while insertion of an intron into an intronless gene suppresses R-loop accumulation and its deleterious impact on transcription and recombination in yeast. Recruitment of the spliceosome onto the mRNA, but not splicing per se, is shown to be critical to attenuate R-loop formation and transcription-associated genetic instability. Genome-wide analyses in a number of distant species differing in their intron content, including human, further revealed that intron-containing genes and the intron-richest genomes are best protected against R-loop accumulation and subsequent genetic instability. Our results thereby provide a possible rationale for the conservation of introns throughout the eukaryotic lineage.

Chávez-Rodriguéz, M, Dias L, Simoes S, Seixas J, Hawkes A, Szklo A, Lucena A.  2017.  Modelling the role of natural gas in the Southern Cone of Latin America. Applied Energy. 201(1):219-239.
Ferreira, J, Santos T, Pereira P, Corvo MC, Queiroz JA, Sousa F, Cruz C.  2017.  Naphthalene amine support for G-quadruplex isolation. Analyst. 142(16):2982-2994.: Royal Society of Chemistry AbstractWebsite

G-quadruplex (G4) is involved in many biological processes, such as telomere function, gene expression and DNA replication. The selective isolation of G4 using affinity ligands that bind tightly and selectively is a valuable strategy for discovering new G4 binders for the separation of G4 from duplexes or the discrimination of G4 structures. In this work, one affinity chromatographic support was prepared using a naphthalene amine as a G4 binder. The ligand was immobilized on epoxy-activated Sepharose CL-6B using a long spacer arm and was characterized by HR-MAS spectroscopy. The supercoiled (sc) isoform of pVAX1-LacZ and pVAX1-G4 was isolated from a native sample. Also, the recovery and isolation of the plasmid isoforms from Escherichia coli lysate samples were achieved using an ionic gradient with different concentrations of NaCl in 10 mM Tris-HCl (pH 7.4). The retention times of different DNA/single strand sequences that can form G4, such as, c-MYC, c-kit1, c-kit2, tetrameric, telomeric (23AG), thrombin aptamer (TBA) and 58Sγ3 in this support were evaluated. Our experimental results suggest that the support exhibits selectivity for parallel c-MYC and c-kit1 G4s. In vitro transcription was performed using purified sc pVAX1-G4 and pPH600 to induce G4 formation and circular dichroism (CD) analysis confirmed that both transcripts adopt a parallel G4 topology.

Mancio-Silva, L, Slavic K, Ruivo MGT, Grosso AR, Modrzynska KK, Vera IM, Sales-dias J, Gomes AR, Macpherson CR, Crozet P, Adamo M, Baena-gonzalez E, Tewari R, Llinás M, Billker O, Mota MM.  2017.  Nutrient sensing modulates malaria parasite virulence. Nature. : Nature Publishing Group AbstractWebsite

The lifestyle of intracellular pathogens, such as malaria parasites, is intimately connected to that of their host, primarily for nutrient supply. Nutrients act not only as primary sources of energy but also as regulators of gene expression, metabolism and growth, through various signalling networks that enable cells to sense and adapt to varying environmental conditions. Canonical nutrient-sensing pathways are presumed to be absent from the causative agent of malaria, Plasmodium, thus raising the question of whether these parasites can sense and cope with fluctuations in host nutrient levels. Here we show that Plasmodium blood-stage parasites actively respond to host dietary calorie alterations through rearrangement of their transcriptome accompanied by substantial adjustment of their multiplication rate. A kinome analysis combined with chemical and genetic approaches identified KIN as a critical regulator that mediates sensing of nutrients and controls a transcriptional response to the host nutritional status. KIN shares homology with SNF1/AMPKα, and yeast complementation studies suggest that it is part of a functionally conserved cellular energy-sensing pathway. Overall, these findings reveal a key parasite nutrient-sensing mechanism that is critical for modulating parasite replication and virulence.

Lopes, J, Rocha J, Redondo L, Cruz J.  2017.  Particle Accelerator Focus Automation. particle_accelerator_focus_automation.pdf
dos Santos, R, Carvalho AL, Roque ACA.  2017.  Renaissance of protein crystallization and precipitation in biopharmaceuticals purification. Biotechnology Advances. 35:–., Number 1: Elsevier Inc. AbstractWebsite

The current chromatographic approaches used in protein purification are not keeping pace with the increasing biopharmaceutical market demand. With the upstream improvements, the bottleneck shifted towards the downstream process. New approaches rely in Anything But Chromatography methodologies and revisiting former techniques with a bioprocess perspective. Protein crystallization and precipitation methods are already implemented in the downstream process of diverse therapeutic biological macromolecules, overcoming the current chromatographic bottlenecks. Promising work is being developed in order to implement crystallization and precipitation in the purification pipeline of high value therapeutic molecules. This review focuses in the role of these two methodologies in current industrial purification processes, and highlights their potential implementation in the purification pipeline of high value therapeutic molecules, overcoming chromatographic holdups.