Redox-Polymer-Wired [NiFeSe] Hydrogenase Variants with Enhanced O2 Stability for Triple-Protected High-Current-Density H2-Oxidation Bioanodes

Variants of the highly active [NiFeSe] hydrogenase from D. vulgaris Hildenborough that exhibit enhanced O2 tolerance were used as H2-oxidation catalysts in H2/O2 biofuel cells. Two [NiFeSe] variants were electrically wired by means of low-potential viologen-modified redox polymers and evaluated with respect to H2-oxidation and stability against O2 in the immobilized state. The two variants showed maximum current densities of (450±84) μA cm−2 for G491A and (476±172) μA cm−2 for variant G941S on glassy carbon electrodes and a higher O2 tolerance than the wild type. In addition, the polymer protected the enzyme from O2 damage and high-potential inactivation, establishing a triple protection for the bioanode. The use of gas-diffusion bioanodes provided current densities for H2-oxidation of up to 6.3 mA cm−2. Combination of the gas-diffusion bioanode with a bilirubin oxidase-based gas-diffusion O2-reducing biocathode in a membrane-free biofuel cell under anode-limiting conditions showed unprecedented benchmark power densities of 4.4 mW cm−2 at 0.7 V and an open-circuit voltage of 1.14 V even at moderate catalyst loadings, outperforming the previously reported system obtained with the [NiFeSe] wild type and the [NiFe] hydrogenase from D. vulgaris Miyazaki F.inpres

Technological-regulatory interface: development of a drug of biological origin for the treatment of chronic ulcers with a high volume of exudate

La infección de una herida y la presencia de exudado contribuyen al retraso en la cicatrización. La infección se produce por bacterias formadoras de biofilm, estrategia que les confiere resistencia a antibióticos, desinfectantes y a la respuesta inmune. La ausencia de tratamientos específicos y accesibles en el sistema público de salud lleva a la aplicación de tratamientos paliativos, que impiden al paciente permanecer ambulante disminuyendo su calidad de vida. Por tratarse de una enfermedad crónica recidivante, con alto requerimiento de recursos, representa una problemática en salud pública. Como tratamiento alternativo el uso de sobrenadante de Lactobacillus plantarum (LAPS) está avalado por reportes científicos publicados desde 2012; el mismo posee metabolitos con actividad antipatogénica y procicatrizante que actúan de manera sinérgica, lo que convierte a esta mezcla compleja en un único Ingrediente Farmacéutico Activo (IFA). El desafío consistió en desarrollar un medicamento de uso tópico que vehiculice LAPS, conservando su actividad y permitiendo el manejo de elevado volumen de exudado, para ofrecer un tratamiento personalizado al paciente, utilizando métodos de producción se realizados acorde a la normativa vigente, a escala laboratorio. Todos se diseñaron bajo principios de (P+L) y Química Verde, para contribuir en el aporte de productos amigables con el ambiente.The infection of a wound and the presence of new exudate to the delay in the healing. The infection is produced by biofilm-forming bacteria, a strategy that confers resistance to antibiotics, disinfectants and the immune response. The absence of specific and accessible treatments in the public health system leads to the application of palliative treatments, which prevent the patient from remaining ambulatory, reducing their quality of life. Because it is a chronic relapsing disease, with a high requirement of resources, it represents a problem in public health. As an alternative treatment with the use of Lactobacillus plantarum supernatant (LAPS) is available by scientific reports published since 2012; it has metabolites with antipathogenic and procicatrizing activity that act synergistically, which turns this complex mixture into a single Active Pharmaceutical Ingredient (API). The challenge consisted in developing a drug for topical use that conveys LAPS, preserving its activity and allowing the management of a high volume of exudate, to offer a personalized treatment to the patient, using production methods that were carried out according to current regulations, at laboratory scale. All were designed under the principles of (P + L) and Green Chemistry, to contribute to the contribution of environmentally friendly products.Fil: Zacarias Chamorro, Cynthia Adriana. Universidad Nacional de Asunción; ParaguayFil: Sesto Cabral, María Eugenia. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; ArgentinaFil: Fretes de Aquino, Sonia Lorena. Universidad Nacional de Asunción; Paragua

Technological-regulatory interface: development of a drug of biological origin for the treatment of chronic ulcers with a high volume of exudate

La infección de una herida y la presencia de exudado contribuyen al retraso en la cicatrización. La infección se produce por bacterias formadoras de biofilm, estrategia que les confiere resistencia a antibióticos, desinfectantes y a la respuesta inmune. La ausencia de tratamientos específicos y accesibles en el sistema público de salud lleva a la aplicación de tratamientos paliativos, que impiden al paciente permanecer ambulante disminuyendo su calidad de vida. Por tratarse de una enfermedad crónica recidivante, con alto requerimiento de recursos, representa una problemática en salud pública. Como tratamiento alternativo el uso de sobrenadante de Lactobacillus plantarum (LAPS) está avalado por reportes científicos publicados desde 2012; el mismo posee metabolitos con actividad antipatogénica y procicatrizante que actúan de manera sinérgica, lo que convierte a esta mezcla compleja en un único Ingrediente Farmacéutico Activo (IFA). El desafío consistió en desarrollar un medicamento de uso tópico que vehiculice LAPS, conservando su actividad y permitiendo el manejo de elevado volumen de exudado, para ofrecer un tratamiento personalizado al paciente, utilizando métodos de producción se realizados acorde a la normativa vigente, a escala laboratorio. Todos se diseñaron bajo principios de (P+L) y Química Verde, para contribuir en el aporte de productos amigables con el ambiente.The infection of a wound and the presence of new exudate to the delay in the healing. The infection is produced by biofilm-forming bacteria, a strategy that confers resistance to antibiotics, disinfectants and the immune response. The absence of specific and accessible treatments in the public health system leads to the application of palliative treatments, which prevent the patient from remaining ambulatory, reducing their quality of life. Because it is a chronic relapsing disease, with a high requirement of resources, it represents a problem in public health. As an alternative treatment with the use of Lactobacillus plantarum supernatant (LAPS) is available by scientific reports published since 2012; it has metabolites with antipathogenic and procicatrizing activity that act synergistically, which turns this complex mixture into a single Active Pharmaceutical Ingredient (API). The challenge consisted in developing a drug for topical use that conveys LAPS, preserving its activity and allowing the management of a high volume of exudate, to offer a personalized treatment to the patient, using production methods that were carried out according to current regulations, at laboratory scale. All were designed under the principles of (P + L) and Green Chemistry, to contribute to the contribution of environmentally friendly products.Fil: Zacarias Chamorro, Cynthia Adriana. Universidad Nacional de Asunción; ParaguayFil: Sesto Cabral, María Eugenia. Universidad Nacional de Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Biotecnología Farmacéutica y Alimentaria; ArgentinaFil: Fretes de Aquino, Sonia Lorena. Universidad Nacional de Asunción; Paragua

Welfare in farmed decapod crustaceans, with particular reference to Penaeus vannamei

The farming of decapod crustaceans is a key economic driver in many countries, with production reaching around 9.4 million tonnes (USD 69.3 billion) in 2018. These efforts are currently dominated by the farming of Pacific whiteleg shrimp, Penaeus vannamei, which translates into approximately 167 billion farmed P. vannamei being harvested annually. Further production growth is expected in the future and hence the need for more research into its health and welfare is required. Herein, from an extensive survey of the available literature, we scrutinise farming practices and the challenges associated with the production of P. vannamei from an animal-centric welfare perspective (1), we propose potential welfare indicators (2) and we critically review current scientific evidence of sentience in penaeid shrimp among other commercially important decapods (3), since it is plausible that in the near future not only the largest, but in fact all decapod crustaceans will receive welfare protection. This review highlights that despite the wide knowledge on crustacean stress physiology and immunology as well as disease control, still little is known about some key parameters related to the five welfare dimensions. We recommend that further research should focus on developing a systematic integrated welfare assessment encompassing all the different aspects of the crustaceans farming and life cycle up to slaughter. Furthermore, direct and indirect species-specific operational welfare indicators should be developed for all decapod crustaceans currently farmed, similar to the ones suggested in this review for P. vannamei

ATP synthesis coupled to the electroenzymatic activity of a hydrogenase immobilized at an electrode/biomimetic membrane interface

Trabajo presentado en el XXIV International Symposium on Bioelectrochemistry and Bioenergetics (BES 2017), celebrado en Lyon del 3 al 7 de julio de 2017.Cells generate energy by coupling a proton gradient across a phospholipid bilayer membrane with the activity of a cross-membrane ATP synthase enzyme. In an effort to mimic this process in an artificial environment, we show that ATP can be efficiently produced starting from molecular hydrogen as a fuel. The proton concentration in an electrode/phospholipid bilayer interface can be controlled and monitorised electrochemically by immobilizing the membrane-bound [NiFeSe]-hydrogenase from Desulfovibrio vulgaris Hildenborough.1 The electro-enzymatic oxidation of H2 generated a proton gradient across the supported biomimetic membrane that can be coupled to the in vitro synthesis of ATP by reconstituting ATP-synthase from E. coli on the biomimetic system.2N

In situ determination of photobioproduction of H2 by In2S3 - [NiFeSe] Hydrogenase from D. vulgaris Hildenborough using only visible light

Trabajo presentado en la NanoGe September Meeting, celebrada en Berlín del 5 al 13 de septiembre de 2016.The energy of the conduction band of In2S3is high enough to supply the hydrogenase with photoexcited electrons for H2 production. Direct electron transfer (DET) between the conduction band and the distal cluster of hydrogenase is aimed to obtain photocatalytic production of hydrogen. The photocatalytic activity of soluble form of the Dv-SeHase incubated previously with In2S3 particles was measured by membrane-inlet mass spectrometry connected to an anaerobic vessel with no gas phase, under visible light irradiation.Thanks to Spanish MINECO CTQ2012-32448 Project and BES-2013-064099 Contract.N

In Situ Determination of Photobioproduction of H2 by In2S3-[NiFeSe] Hydrogenase from Desulfovibrio vulgaris Hildenborough Using Only Visible Light

An interesting strategy for photocatalytic production of hydrogen from water and sunlight is the formation of a hybrid photocatalyst that combines an inorganic semiconductor able to absorb in the visible light spectral range with an enzymatic catalyst for reducing protons. In this work we study how to optimize the interfacing of In2S3 particles with the soluble form of [NiFeSe] hydrogenase from Desulfovibrio vulgaris Hildenborough by means of its initial H2 photoproduction rate. The kinetics of the photocatalytic process was studied by membrane-inlet mass spectrometry, in order to optimize the interaction between both components of the hybrid photocatalyst. Membrane-inlet mass spectrometry allows measuring in the same experiment, for comparison, the rate of H2 production by the photocatalyst hybrid directly in the aqueous solution in real time and the result of a standard assay of the hydrogenase activity. An incubation period of 6 h with mild stirring of hydrogenase with In2S3 particles was necessary for optimal interaction of the enzyme molecules with the porous surface of the semiconductor. A turnover frequency of the NiFeSe hydrogenase (TOFHase) for H2 photobioproduction of 986 s–1 was measured under the optimized conditions. This means that the immobilized hydrogenase has a photocatalytic efficiency for H2 generation which is 94% of that obtained in the standard specific activity test of H2 production using reduced methyl viologen as an electron donor.This work was funded by the Spanish MINECO (projects CTQ2015-71290-R and ENE2013-46624-C4-1-R) and by Fundação para a Ciência e a Tecnologia (Portugal) (Grants UID/Multi/04551/2013 and PTDC/BBB-BEP/2885/2014 and Ph.D. fellowship SFRH/BPD/xxx/201x). C.T. thanks the Spanish MINECO for her BES-2013-064099 contract.Peer reviewe

Data for 'Fast CO2 hydration kinetics impair heterogeneous but improve enzymatic CO2 reduction catalysis'

Main - contains all Electrochemical, Finite Element Modelling outputs, SEM, QCM, product quantification and image data related to main text sorted by respective figure. Extended Data - contains all QCM, SEM, Solution assay data, Electrochemical experiments, Finite Element Modelling outputs, SEM, QCM, product quantification and image data related to the extended dataset sorted by respective figure. SI Data - contains all Electrochemical, Finite Element Modelling outputs, product quantification, SEM, DLS and image data related to the Supplementary Information sorted by respective figure. Wilbur Anderson Assay Python Script- contains License file, Readme and script for solution assay simulatio

Induction of a proton gradient across a gold-supported biomimetic membrane by electroenzymatic H2 oxidation

[EN] Energy-transduction mechanisms in living organisms, such as photosynthesis and respiration, store light and chemical energy in the form of an electrochemical gradient created across a lipid bilayer. Herein we show that the proton concentration at an electrode/phospholipid-bilayer interface can be controlled and monitored electrochemically by immobilizing a membrane-bound hydrogenase. Thus, the energy derived from the electroenzymatic oxidation of H2 can be used to generate a proton gradient across the supported biomimetic membrane. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.This research was funded by the Spanish MINECO (project CTQ2012-32448) and by the Fundação para a Ciência e a Tecnologia (project PTDC/BBB-BEP/0934/2012). O.G.-S. thanks MINECO for an FPI grant.Peer Reviewe

Raw Data supporting article: Reversible and selective interconversion of hydrogen and carbon dioxide into formate by a semi-artificial formate hydrogenlyase mimic

Raw data and corresponding data analysis (Microsoft Office Excel, Origin) supporting Journal of American Chemical Society publication: "Reversible and Selective Interconversion of Hydrogen and Carbon Dioxide into Formate by a Semiartificial Formate Hydrogenlyase Mimic". Data include: three-electrode and two-electrode electrochemistry and electrolysis, colloidal particle system experiments (with indium tin oxide nanoparticles, cytochrome c, denatured enzymes), data analysis and product quantification