Stepwise pathway for early evolutionary assembly of dissimilatory sulfite and sulfate reduction

Funding Information: FLS and SN acknowledge support from the Wiener Wissenschafts, Forschungs- und Technologiefonds (Austria) through the grant VRG15-007. FLS gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation program (grant agreement 803768). IACP acknowledges support from Fundação para a Ciência e Tecnologia (Portugal) through grants PTDC/BIA-MIC/6512/2014 and PTDC/BIA-BQM/29118/2017, R&D unit MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020), and LS4FUTURE Associated Laboratory (LA/P/0087/2020). The computational results of this work have been achieved using the Life Science Compute Cluster (LiSC) of the University of Vienna. Funding Information: FLS and SN acknowledge support from the Wiener Wissenschafts, Forschungs- und Technologiefonds (Austria) through the grant VRG15-007. FLS gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation program (grant agreement 803768). IACP acknowledges support from Fundação para a Ciência e Tecnologia (Portugal) through grants PTDC/BIA-MIC/6512/2014 and PTDC/BIA-BQM/29118/2017, R&D unit MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020), and LS4FUTURE Associated Laboratory (LA/P/0087/2020). The computational results of this work have been achieved using the Life Science Compute Cluster (LiSC) of the University of Vienna. Publisher Copyright: © 2023, The Author(s).Microbial dissimilatory sulfur metabolism utilizing dissimilatory sulfite reductases (Dsr) influenced the biochemical sulfur cycle during Earth’s history and the Dsr pathway is thought to be an ancient metabolic process. Here we performed comparative genomics, phylogenetic, and synteny analyses of several Dsr proteins involved in or associated with the Dsr pathway across over 195,000 prokaryotic metagenomes. The results point to an archaeal origin of the minimal DsrABCMK(N) protein set, having as primordial function sulfite reduction. The acquisition of additional Dsr proteins (DsrJOPT) increased the Dsr pathway complexity. Archaeoglobus would originally possess the archaeal-type Dsr pathway and the archaeal DsrAB proteins were replaced with the bacterial reductive-type version, possibly at the same time as the acquisition of the QmoABC and DsrD proteins. Further inventions of two Qmo complex types, which are more spread than previously thought, allowed microorganisms to use sulfate as electron acceptor. The ability to use the Dsr pathway for sulfur oxidation evolved at least twice, with Chlorobi and Proteobacteria being extant descendants of these two independent adaptations.publishersversioninpres

Comproportionation of CO2 and Cellulose to Formate Using a Floating Semiconductor-Enzyme Photoreforming Catalyst

Funding Information: We would like to thank the European Research Council (ERC) for a Proof of Concept Grant (SolReGen; to E.L. and E.R.) and a Consolidator Grant (MatEnSAP; to M.M. and E.R.), the Swiss National Science Foundation (Early Postdoc Fellowship: P2EZP2 191791 to E.L.) as well as the National Science and Engineering Research Council of Canada (NSERC) for a Postdoctoral Fellowship (S.L.). We thank also Fundação para a Ciência e Tecnologia (Portugal) for fellowship DFA/BD/7897/2020 (R.M.), grant PTDC/BII-BBF/2050/2020 (I.A.C.P.), MOSTMICRO-ITQB unit (UIDB/04612/2020 and UIDP/04612/2020) and Associated Laboratory LS4FUTURE (LA/P/0087/2020). Ariffin Mohamad Annuar, Subhajit Bhattacharjee, Dongseok Kim (University of Cambridge) and Victor Mougel (ETH Zürich) are acknowledged for helpful discussions. Funding Information: We would like to thank the European Research Council (ERC) for a Proof of Concept Grant (SolReGen; to E.L. and E.R.) and a Consolidator Grant (MatEnSAP; to M.M. and E.R.), the Swiss National Science Foundation (Early Postdoc Fellowship: P2EZP2 191791 to E.L.) as well as the National Science and Engineering Research Council of Canada (NSERC) for a Postdoctoral Fellowship (S.L.). We thank also Fundação para a Ciência e Tecnologia (Portugal) for fellowship DFA/BD/7897/2020 (R.M.), grant PTDC/BII‐BBF/2050/2020 (I.A.C.P.), MOSTMICRO‐ITQB unit (UIDB/04612/2020 and UIDP/04612/2020) and Associated Laboratory LS4FUTURE (LA/P/0087/2020). Ariffin Mohamad Annuar, Subhajit Bhattacharjee, Dongseok Kim (University of Cambridge) and Victor Mougel (ETH Zürich) are acknowledged for helpful discussions. Publisher Copyright: © 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.Formate production via both CO2 reduction and cellulose oxidation in a solar-driven process is achieved by a semi-artificial biohybrid photocatalyst consisting of immobilized formate dehydrogenase on titanium dioxide (TiO2|FDH) producing up to 1.16±0.04 mmolformate g (Formula presented.) −1 in 24 hours at 30 °C and 101 kPa under anaerobic conditions. Isotopic labeling experiments with 13C-labeled substrates support the mechanism of stoichiometric formate formation through both redox half-reactions. TiO2|FDH was further immobilized on hollow glass microspheres to perform more practical floating photoreforming allowing vertical solar light illumination with optimal light exposure of the photocatalyst to real sunlight. Enzymatic cellulose depolymerization coupled to the floating photoreforming catalyst generates 0.36±0.04 mmolformate per m2 irradiation area after 24 hours. This work demonstrates the synergistic solar-driven valorization of solid and gaseous waste streams using a biohybrid photoreforming catalyst in aqueous solution and will thus provide inspiration for the development of future semi-artificial waste-to-chemical conversion strategies.publishersversionpublishe

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

A photoelectrochemical-thermoelectric device for semi-artificial CO2 fixation employing full solar spectrum utilization

Funding Information: We acknowledge support from the Leverhulme Trust for an Early Career Fellowship ( ECF-2021-072 to S.J.C. and ECF-2022-392 to L.S.), the Isaac Newton Trust (20.08(r) to S.J.C. and 22.08(c) to L.S.), the Cambridge Trust ( Cambridge Thai Foundation Award to C.P.), a Trinity-Henry Barlow Scholarship (to C.P.), the Cambridge Philosophical Society (to C.P.), the Program Management Unit for Human Resources and Institutional Development, Research, and Innovation ( B16F640166 to C.P.), the EPSRC Graphene CDT ( EP/L016087/1 to V.M.B.), St John\u2019s College Cambridge ( Title A Research Fellowship to V.A.), the European Research Council (ERC) for a Consolidator Grant (MatEnSAP, 682833 to E.R.) and a UKRI/ERC Advanced Grant ( EP/X030563/1 to E.R.), the Funda\u00E7\u00E3o para a Ci\u00EAncia e a Tecnologia (FCT, Portugal) for fellowship DFA/BD/7897/2020 (to R.R.M.), grant PTDC/BII-BBF/2050/2020 (to I.A.C.P.) and MOSTMICRO-ITQB unit ( UIDB/04612/2020 and UIDP/04612/2020 ), and Associated Laboratory LS4FUTURE ( LA/P/0087/2020 ). Funding Information: We acknowledge support from the Leverhulme Trust for an Early Career Fellowship (ECF-2021-072 to S.J.C. and ECF-2022-392 to L.S.), the Isaac Newton Trust (20.08(r) to S.J.C. and 22.08(c) to L.S.), the Cambridge Trust (Cambridge Thai Foundation Award to C.P.), a Trinity-Henry Barlow Scholarship (to C.P.), the Cambridge Philosophical Society (to C.P.), the Program Management Unit for Human Resources and Institutional Development, Research, and Innovation (B16F640166 to C.P.), the EPSRC Graphene CDT (EP/L016087/1 to V.M.B.), St John's College Cambridge (Title A Research Fellowship to V.A.), the European Research Council (ERC) for a Consolidator Grant (MatEnSAP, 682833 to E.R.) and a UKRI/ERC Advanced Grant (EP/X030563/1 to E.R.), the Funda\u00E7\u00E3o para a Ci\u00EAncia e a Tecnologia (FCT, Portugal) for fellowship DFA/BD/7897/2020 (to R.R.M.), grant PTDC/BII-BBF/2050/2020 (to I.A.C.P.) and MOSTMICRO-ITQB unit (UIDB/04612/2020 and UIDP/04612/2020), and Associated Laboratory LS4FUTURE (LA/P/0087/2020). Conceptualization, S.J.C. C.P. and E.R; investigation, S.J.C. C.P. V.M.B. L.S. and R.R.M.; resources, R.R.M. and I.A.C.P.; formal analysis, S.J.C. C.P. V.M.B. L.S. R.R.M.; writing \u2013 original draft, S.J.C. C.P. and E.R.; writing \u2013 review & editing, V.A. L.S. R.R.M. and I.A.C.P.; visualization, S.J.C. C.P. V.A. and L.S.; supervision, E.R.; funding acquisition, S.J.C. I.A.C.P. and E.R. The authors declare no competing interests. Publisher Copyright: © 2024 The Author(s)Natural and most artificial photosynthesis systems utilize a pair of light absorbers to convert CO2 into sugar and fuels. However, much of the solar energy is lost as unabsorbed (mainly infrared [IR]) irradiation and thermalization heat, limiting efficiency. Here, we show that a thermoelectric (TE) generator can harvest this waste heat toward unassisted CO2 reduction with a water-oxidizing BiVO4 photoanode upon irradiation by concentrated sunlight. We employ the enzyme formate dehydrogenase (FDh) as a model catalyst to achieve selective CO2-to-formate conversion with minimal overpotential. The catalytic activity of the FDh cathode and BiVO4 photoanode benefits from solar heating, enabling the bias-free semi-artificial FDh-TE-BiVO4 device to attain a 97% faradic yield for formate production under 3-sun irradiation. This work demonstrates unassisted CO2 reduction coupled to water oxidation using only a single semiconductor light absorber through effective waste heat utilization, overcoming the challenges of (non-)complementary light absorption and IR losses in both natural and artificial photosynthesis.proofinpres

Energy flux couples sulfur isotope fractionation to proteomic and metabolite profiles in Desulfovibrio vulgaris

Funding Information: We thank S. Moore and D. Fike for bulk sulfur isotope analyses (WashU); M. Seuss for assistance with lipid\u2010H isotope analyses (Bradley lab, WashU); X. Feng (Dartmouth) and M. Osburn (Northwestern) for water H\u2010isotope analyses; and A. Sessions and J. Adkins (CalTech) for access to HPLC\u2010ICP\u2010MS. Metabolite analyses were performed by the Proteomics & Mass Spectrometry Facility at the Danforth Plant Science Center (St. Louis, MO, USA). Funding was provided: by NASA Exobiology Award 13\u2010EXO13\u20100082 (ASB, WDL, JW), NSF\u2010EAR Award 1928309 (WDL), Washington University in St. Louis Department of Earth & Planetary Sciences Fossett Fellowship (WDL), the Walter and Constance Burke Fund at Dartmouth College (WDL), and the Fulbright\u2014Bunge & Born\u2014Williams Foundation Scholarship Program (FJB), Funda\u00E7\u00E3o para a Ci\u00EAncia e Tecnologia (Portugal) through R&D unit MOSTMICRO\u2010ITQB (UIDB/04612/2020 and UIDP/04612/2020) and LS4FUTURE Associated Laboratory (LA/P/0087/2020) (IACP), NSF GRFP [2017250547] (SP). Funding Information: We thank S. Moore and D. Fike for bulk sulfur isotope analyses (WashU); M. Seuss for assistance with lipid-H isotope analyses (Bradley lab, WashU); X. Feng (Dartmouth) and M. Osburn (Northwestern) for water H-isotope analyses; and A. Sessions and J. Adkins (CalTech) for access to HPLC-ICP-MS. Metabolite analyses were performed by the Proteomics & Mass Spectrometry Facility at the Danforth Plant Science Center (St. Louis, MO, USA). Funding was provided: by NASA Exobiology Award 13-EXO13-0082 (ASB, WDL, JW), NSF-EAR Award 1928309 (WDL), Washington University in St. Louis Department of Earth & Planetary Sciences Fossett Fellowship (WDL), the Walter and Constance Burke Fund at Dartmouth College (WDL), and the Fulbright\u2014Bunge & Born\u2014Williams Foundation Scholarship Program (FJB), Funda\u00E7\u00E3o para a Ci\u00EAncia e Tecnologia (Portugal) through R&D unit MOSTMICRO-ITQB (UIDB/04612/2020 and UIDP/04612/2020) and LS4FUTURE Associated Laboratory (LA/P/0087/2020) (IACP), NSF GRFP [2017250547] (SP). Publisher Copyright: © 2024 The Authors. Geobiology published by John Wiley & Sons Ltd.Microbial sulfate reduction is central to the global carbon cycle and the redox evolution of Earth's surface. Tracking the activity of sulfate reducing microorganisms over space and time relies on a nuanced understanding of stable sulfur isotope fractionation in the context of the biochemical machinery of the metabolism. Here, we link the magnitude of stable sulfur isotopic fractionation to proteomic and metabolite profiles under different cellular energetic regimes. When energy availability is limited, cell-specific sulfate respiration rates and net sulfur isotope fractionation inversely covary. Beyond net S isotope fractionation values, we also quantified shifts in protein expression, abundances and isotopic composition of intracellular S metabolites, and lipid structures and lipid/water H isotope fractionation values. These coupled approaches reveal which protein abundances shift directly as a function of energy flux, those that vary minimally, and those that may vary independent of energy flux and likely do not contribute to shifts in S-isotope fractionation. By coupling the bulk S-isotope observations with quantitative proteomics, we provide novel constraints for metabolic isotope models. Together, these results lay the foundation for more predictive metabolic fractionation models, alongside interpretations of environmental sulfur and sulfate reducer lipid-H isotope data.publishersversionpublishe

A novel NADH dehydrogenase family widespread in bacteria

info:eu-repo/semantics/nonPublishe

ORGANOHALIDE RESPIRATION: STUDY OF THE MEMBRANE PROTEIN COMPLEX RESPONSIBLE FOR THE REDUCTION OF HALOGENATED COMPOUNDS

Organohalide respiration (OHR) is a bacterial anaerobic respiratory process in which halogenated compounds are used as terminal electron acceptors. Desulfitobacterium and Dehalobacter, paradigmatic organohalide-respiring bacteria (OHRB), harbour the pceABCT gene cluster, representing one model system in OHR. While both Dehalobacter restrictus and Desulfitobacterium hafniense strain TCE1 dechlorinate tetrachloroethene (PCE), 3,5-dichlorophenol (DCP) is dechlorinated by D. hafniense strain DCB-2. The relatively high DNA sequence identity (70%) and similar gene composition and regulation between the pceABCT and dcpABCT gene clusters triggered our interest in studying the possible co-transcription of the genes, in establishing stoichiometric relationships between the corresponding proteins, and in trying to decipher the reductive dehalogenase (RDH) protein complex from the cytoplasmic membrane of those bacteria. Gene co-transcription was investigated by a combination of RNA extraction and RT-qPCR, while the stoichiometry of the proteins is analyzed via quantitative proteomics. Clear-Native PAGE technology combined with an in-gel reductive dehalogenase activity assay are established to identify proteins from the RDH complex. The transcriptional analysis conducted on D. hafniense strain DCB-2 showed that dcp gene cluster is actively up-regulated by 3,5-DCP. At protein level, reference peptides were defined for PceA, B, C and T from D. restrictus and D. hafniense strain TCE1 and they will be applied for measuring the relative stoichiometry of the targeted proteins. Furthermore, preliminary results from CN-PAGE analysis suggest that the PCE reductive dehalogenase (PceA) catalytic subunit is part of a ~150 kDa protein complex in D. restrictus. At transcriptional level the results suggest that dcp gene cluster shows an operon structure. However, the possibility of additional promoters regulating the transcription of individual genes within the operon are under investigation. At protein level, the identification of the RDH complex allows us to address the question of the proteins that are associated with PceA

Formate dehydrogenases reduce CO2 rather than HCO3- : an electrochemical demonstration

International audienceMo/W formate dehydrogenases catalyze the reversible reduction of CO 2 species to formate. It is thought that the substrate is CO 2 and not a hydrated species like HCO-3 , but there is still no indisputable evidence for this, in spite of the extreme importance of the nature of the substrate for mechanistic studies. We devised a simple electrochemical method to definitely demonstrate that the substrate of formate dehydrogenases is indeed CO 2

Occupational behaviour study in the retail sector

The health, safety, and well-being of employees, service providers, and customers are important priorities for retail companies. Based on this principle, an intelligent system that contributes to the reduction of accidents at work will be developed, monitoring risk control, preventing work-related illnesses, promoting a culture of zero accidents, and seeking to ensure the health of employees, customers, and stakeholders. In order to achieve such goals, it is necessary to determine the local and global variables (internal and external) that feed the system. This study comprises the first strategy applied to collect the local variables involved in the problem. To obtain this, a data analysis study in a retail store was performed. Data analysis procedures were performed namely clustering analysis with algorithm k-means, correlation procedures, like Pearson coefficient and matrix of correlation, and relationship analysis with parallel coordinate graphs. From the preliminary results, it is possible to indicate a set of local variables that have influence in the occupational behavior and accidents at work.info:eu-repo/semantics/publishedVersio