A5111493694- Metalloenzymes and iron-sulfur proteins
- Microbial Metabolic Engineering and Bioproduction
- Electrocatalysts for Energy Conversion
- Biofuel production and bioconversion
- Advanced battery technologies research
- Enzyme Catalysis and Immobilization
- Bacterial Genetics and Biotechnology
- Hydrogen Storage and Materials
- Anaerobic Digestion and Biogas Production
- Microbial Fuel Cells and Bioremediation
- Enzyme Structure and Function
- Enzyme Production and Characterization
- Asymmetric Hydrogenation and Catalysis
- Clostridium difficile and Clostridium perfringens research
- Fungal and yeast genetics research
- Catalysis for Biomass Conversion
- Gut microbiota and health
- Spectroscopy and Quantum Chemical Studies
- Magnesium Alloys: Properties and Applications
- Microbial bioremediation and biosurfactants
- Corrosion Behavior and Inhibition
- Catalysis and Hydrodesulfurization Studies
- CO2 Reduction Techniques and Catalysts
- Porphyrin Metabolism and Disorders
- Glycosylation and Glycoproteins Research
Centre National de la Recherche Scientifique
2011-2022
Institut National des Sciences Appliquées de Toulouse
2003-2022
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2021-2022
Université Toulouse III - Paul Sabatier
2009-2021
Université de Toulouse
2009-2021
Laboratoire d'Ingénierie des Systèmes Biologiques et des Procédés
2011-2021
Institut National des Sciences Appliquées de Lyon
2012-2013
TRANSFORM
2012
Biotechnology Institute
2011
Institut National de la Recherche Agronomique du Niger
2011
The genes encoding the 1,3-propanediol (1,3-PD) operon of Clostridium butyricum VPI1718 were characterized from a molecular and biochemical point view. This is composed three genes, dhaB1, dhaB2, dhaT. When grown in vitamin B12-free mineral medium with glycerol as carbon source, Escherichia coli expressing dhaT produces 1,3-PD high dehydratase dehydrogenase activities. dhaB1 dhaB2 encode, respectively, new type its activator protein. deduced proteins DhaB1 DhaB2, calculated masses 88,074...
Abstract A novel three stages continuous fermentation process for the bioproduction of succinic acid at high concentration, productivity and yield using A. succiniciproducens was developed. This combined an integrated membrane‐bioreactor‐electrodialysis system. An energetic characterization during anaerobic cultured in a cell recycle bioreactor done first. The very low value Y ATP obtained suggests that dependent mechanism succinate export is present . Under best culture conditions, biomass...
ABSTRACT The adhE2 gene of Clostridium acetobutylicum ATCC 824, coding for an aldehyde/alcohol dehydrogenase (AADH), was characterized from molecular and biochemical points view. 2,577-bp codes a 94.4-kDa protein. is expressed, as monocistronic operon, in alcohologenic cultures not solventogenic cultures. Primer extension analysis identified two transcriptional start sites 160 215 bp upstream the codon. expression plasmid DG1 mutant C. , cured pSOL1 megaplasmid, restored butanol production...
Clostridium acetobutylicum is not able to grow on glycerol as the sole carbon source since it cannot reoxidize excess of NADH generated by catabolism. Nevertheless, when pSPD5 plasmid, carrying NADH-consuming 1,3-propanediol pathway from C. butyricum VPI 3266, was introduced into DG1, growth achieved, and produced. In order compare physiological behavior recombinant DG1(pSPD5) strain with that natural producer both strains were grown in chemostat cultures source. The same "global behavior"...
ABSTRACT Clostridium acetobutylicum ATCC 824 was selected for the homologous overexpression of its Fe-only hydrogenase and heterologous expressions Chlamydomonas reinhardtii Scenedesmus obliquus HydA1 hydrogenases. The three Strep tag II-tagged hydrogenases were isolated with high specific activities by two-step column chromatography. purified algal evolve hydrogen rates around 700 μmol H 2 min −1 mg , while HydA from C. (HydA Ca ) shows highest activity (5,522 in direction uptake. Further,...
Direct electron transfer between enzymes and electrodes is now commonly achieved, but obtaining protein films that are very stable may be challenging. This particularly crucial in the case of hydrogenases, catalyze biological conversion dihydrogen protons, because instability hydrogenase prevent use these as electrocatalysts H(2) oxidation production biofuel cells photoelectrochemical cells. Here we show two different FeFe hydrogenases (from Chamydomonas reinhardtii Clostridium...
Ruminiclostridium cellulolyticum and Lachnoclostridium phytofermentans (formerly known as Clostridium phytofermentans, respectively) are anaerobic bacteria that developed different strategies to depolymerize the cellulose related plant cell wall polysaccharides. Thus, R. produces large extracellular multi-enzyme complexes termed cellulosomes, while L. secretes in environment some cellulose-degrading enzymes free enzymes. In present study, major cellulase from was introduced a enzyme or...
ABSTRACT Engineering industrial microorganisms for ambitious applications, example, the production of second-generation biofuels such as butanol, is impeded by a lack knowledge primary metabolism and its regulation. A quantitative system-scale analysis was applied to biofuel-producing bacterium Clostridium acetobutylicum , microorganism used solvent. An improved genome-scale model, i Cac967, first developed based on thorough biochemical characterizations 15 key metabolic enzymes extensive...
Carbon monoxide is often described as a competitive inhibitor of FeFe hydrogenases, and it used for probing H2 binding to synthetic or in silico models the active site H-cluster. Yet does not always behave simple inhibitor. Using an original approach which combines accurate electrochemical measurements theoretical calculations, we elucidate mechanism by which, under certain conditions, CO can cause permanent damage Like case oxygen inhibition, reaction with engages entire H-cluster, rather...
Using direct electrochemistry to learn about the mechanism of electrocatalysts and redox enzymes requires that kinetic models be developed. Here we thoroughly discuss interpretation electrochemical signals obtained with adsorbed molecular catalysts can reversibly convert their substrate product. We derive analytical relations between observables (overpotentials for catalysis in each direction, positions, magnitudes features catalytic wave) characteristics cycle (redox properties...
[FeFe]-hydrogenases, HydAs, are unique biocatalysts for proton reduction to H2. However, they suffer from a number of drawbacks biotechnological applications: size, and diversity metal cofactors, oxygen sensitivity. Here we show that HydA Megasphaera elsdenii (MeHydA) displays significant resistance O2. Furthermore, produced shorter version this enzyme (MeH-HydA), lacking the N-terminal domain harboring accessory FeS clusters. As shown by detailed spectroscopic biochemical characterization,...
By analysing the results of experiments carried out with two FeFe hydrogenases and several "channel mutants" a NiFe hydrogenase, we demonstrate that whether or not hydrogen evolution is significantly inhibited by H2 consequence active site chemistry, but rather relates to transport within enzyme.
The mechanism of reaction FeFe hydrogenases with oxygen has been debated. It is complex, apparently very dependent on the details protein structure, and difficult to study using conventional kinetic techniques. Here we build our recent work anaerobic inactivation enzyme [Fourmond et al. Nat. Chem. 2014, 4, 336-342] propose apply a new method for studying this reaction. Using electrochemical measurements turnover rate hydrogenase, could resolve first steps inhibition accurately determine...
Clostridium acetobutylicum is a promising biocatalyst for the renewable production of n-butanol. Several metabolic strategies have already been developed to increase butanol yields, most often based on carbon pathway redirection. However, it has previously demonstrated that activities both ferredoxin-NADP+ reductase and ferredoxin-NAD+ reductase, whose encoding genes remain unknown, are necessary produce NADPH extra NADH needed synthesis under solventogenic conditions. Here, we purify,...
Bacterial metabolism is characterized by a remarkable capacity to rapidly adapt environmental changes. We restructured the central metabolic network in Escherichia coli force higher production of NADPH, and then grew this strain conditions favoring adaptive evolution. A six-fold increase growth was attained that could be attributed multiple clones, after whole genome mutation mapping, specific single mutation. Each clone had an evolved NuoF*(E183A) enzyme respiratory complex I can now...
Clostridium acetobutylicum is a gram-positive, spore-forming, anaerobic bacterium capable of converting various sugars and polysaccharides into solvents (acetone, butanol, ethanol). The sequencing its genome has prompted new approaches to genetic analysis, functional genomics, metabolic engineering develop industrial strains for the production biofuels bulk chemicals. method used in this paper knock-out or knock-in genes C. combines use an antibiotic-resistance gene deletion replacement...