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Michael W W Adams - One of the best experts on this subject based on the ideXlab platform.
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Electricity generation by Pyrococcus furiosus in microbial fuel cells operated at 90°C: Electricity generation by Pyrococcus furiosus
Biotechnology and Bioengineering, 2017Co-Authors: Narendran Sekar, Michael W W Adams, Ramaraja P. RamasamyAbstract:Hyperthermophiles are microorganisms that thrive in extremely hot environments with temperatures near and even above 100°C. They are the most deeply rooted microorganisms on phylogenetic trees suggesting they may have evolved to survive in the early hostile earth. The simple respiratory systems of some of these hyperthermophiles make them potential candidates to develop microbial fuel cells (MFC) that can generate power at temperatures approaching the boiling point. We explored extracellular electron transfer in the hyperthermophilic archaeon Pyrococcus furiosus (Pf) by studying its ability to generate electricity in a two-chamber MFC. Pf growing in defined medium functioned as an anolyte in a MFC operated at 90°C, generating a maximum current density of 2 A m−2 and a peak power density of 225 mW m−2 without the addition of any external redox mediator. Electron microscopy and electrochemical impedance spectroscopy of the anode with the attached Pf biofilm demonstrated bio-electrochemical behavior that led to electricity generation in the MFC via direct electron transfer. This proof of concept study reveals for the first time that a hyperthermophile such as Pf can generate electricity in MFC at extreme temperatures. Biotechnol. Bioeng. 2017;114: 1419–1427. © 2017 Wiley Periodicals, Inc.
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Production and Application of a Soluble Hydrogenase from Pyrococcus furiosus
Archaea, 2015Co-Authors: Patrick M. Mcternan, Mary E. Walter, Michael W W AdamsAbstract:Hydrogen gas is a potential renewable alternative energy carrier that could be used in the future to help supplement humanity's growing energy needs. Unfortunately, current industrial methods for hydrogen production are expensive or environmentally unfriendly. In recent years research has focused on biological mechanisms for hydrogen production and specifically on hydrogenases, the enzyme responsible for catalyzing the reduction of protons to generate hydrogen. In particular, a better understanding of this enzyme might allow us to generate hydrogen that does not use expensive metals, such as platinum, as catalysts. The soluble hydrogenase I (SHI) from the hyperthermophile Pyrococcus furiosus, a member of the euryarchaeota, has been studied extensively and used in various biotechnological applications. This review summarizes the strategies used in engineering and characterizing three different forms of SHI and the properties of the recombinant enzymes. SHI has also been used in in vitro systems for hydrogen production and NADPH generation and these systems are also discussed.
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The Elemental Sulfur-Responsive Protein (SipA) from the Hyperthermophilic Archaeon Pyrococcus furiosus Is Regulated by Sulfide in an Iron-Dependent Manner
Journal of Bacteriology, 2010Co-Authors: Sonya M. Clarkson, Elizabeth C. Newcomer, Everett G. Young, Michael W W AdamsAbstract:The gene (sipA) encoding the sulfur-induced protein A (PF2025) is highly upregulated during growth of Pyrococcus furiosus on elemental sulfur (S(0)). Expression of sipA is regulated by sulfide, the product of S(0) reduction, but in an iron-dependent manner. SipA is proposed to play a role in intracellular iron sulfide detoxification.
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Operon prediction in Pyrococcus furiosus
Nucleic Acids Research, 2006Co-Authors: Thao Tran, Michael W W Adams, Phuongan Dam, Farris L. Poole, G. Tong ZhouAbstract:Identification of operons in the hyperthermophilic archaeon Pyrococcus furiosus represents an important step to understanding the regulatory mechanisms that enable the organism to adapt and thrive in extreme environments. We have predicted operons in P.furiosus by combining the results from three existing algorithms using a neural network (NN). These algorithms use intergenic distances, phylogenetic profiles, functional categories and gene-order conservation in their operon prediction. Our method takes as inputs the confidence scores of the three programs, and outputs a prediction of whether adjacent genes on the same strand belong to the same operon. In addition, we have applied Gene Ontology (GO) and KEGG pathway information to improve the accuracy of our algorithm. The parameters of this NN predictor are trained on a subset of all experimentally verified operon gene pairs of Bacillus subtilis. It subsequently achieved 86.5% prediction accuracy when applied to a subset of gene pairs for Escherichia coli, which is substantially better than any of the three prediction programs. Using this new algorithm, we predicted 470 operons in the P.furiosus genome. Of these, 349 were validated using DNA microarray data.
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normal mode analysis of Pyrococcus furiosus rubredoxin via nuclear resonance vibrational spectroscopy nrvs and resonance raman spectroscopy
Journal of the American Chemical Society, 2005Co-Authors: Yuming Xiao, Francis E. Jenney, Michael W W Adams, Hongxin Wang, Simon J George, Matt C Smith, W Sturhahn, Jiyong Zhao, Yoshitaka Yoda, Edward I SolomonAbstract:We have used 57Fe nuclear resonance vibrational spectroscopy (NRVS) to study the Fe(Scys)4 site in reduced and oxidized rubredoxin (Rd) from Pyrococcus furiosus (Pf). The oxidized form has also bee...
Wilfred R. Hagen - One of the best experts on this subject based on the ideXlab platform.
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phosphate and arsenate removal efficiency by thermostable ferritin enzyme from Pyrococcus furiosus using radioisotopes
Water Research, 2015Co-Authors: Ana-maria Sevcenco, Hubert Th. Wolterbeek, Monica Paravidino, J S Vrouwenvelder, Mark C M Van Loosdrecht, Wilfred R. HagenAbstract:Oxo-anion binding properties of the thermostable enzyme ferritin from Pyrococcus furiosus were characterized with radiography. Radioisotopes 32P and 76As present as oxoanions were used to measure the extent and the rate of their absorption by the ferritin. Thermostable ferritin proved to be an excellent system for rapid phosphate and arsenate removal from aqueous solutions down to residual concentrations at the picomolar level. These very low concentrations make thermostable ferritin a potential tool to considerably mitigate industrial biofouling by phosphate limitation or to remove arsenate from drinking water.
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The tungsten metallome of Pyrococcus furiosus
Metallomics, 2009Co-Authors: Ana-maria Sevcenco, Peter-leon Hagedoorn, Martijn W. H. Pinkse, Emile Bol, Gerard C. Krijger, Hubert Th. Wolterbeek, Peter Verhaert, Wilfred R. HagenAbstract:The tungsten metallome of the hyperthermophilic archaeon Pyrococcus furiosus has been investigated using electroanalytical metal analysis and native–native 2D-PAGE with the radioactive tungsten isotope 187W (t1/2 = 23.9 h). P. furiosus cells have an intracellular tungsten concentration of 29 μM, of which ca. 30% appears to be free tungsten, probably in the form of tungstate or polytungstates. The remaining 70% is bound by five different tungsten enzymes: formaldehyde ferredoxin oxidoreductase, aldehyde ferredoxin oxidoreductase, glyceraldehyde-3-phosphate ferredoxin oxidoreductase and the tungsten-containing oxidoreductases WOR4 and WOR5. The membrane proteome of P. furiosus is devoid of tungsten. The differential expression, as measured by the tungsten level, of the five soluble tungsten enzymes when the cells are subjected to a cold-shock shows a strong correlation with previously published DNA microarray analyses.
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Direct Bioelectrocatalysis by NADP‐Reducing Hydrogenase from Pyrococcus furiosus
Electroanalysis, 2007Co-Authors: Oleg G. Voronin, Wilfred R. Hagen, Daan J. Van Haaster, Elena E. Karyakina, Arkady A. KaryakinAbstract:The direct bioelectrocatalysis by an NAD(P)-reducing hydrogenase is reported for the first time. In contrast to previous attempts to involve similar enzymes in bioelectrocatalysis [1–4], which were in fact unsuccessful, in our report an effective electrocatalysis by Pyrococcus furiosus hydrogenase is convincingly shown by (i) achievement of the hydrogen equilibrium potential and (ii) a high current of hydrogen oxidation (0.3 mA cm−2 at 100 mV overpotential and at 75 °C). The latter is just a few times lower compared to enzyme electrodes based on NAD(P)-independent hydrogenases.
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A highly thermostable ferritin from the hyperthermophilic archaeal anaerobe Pyrococcus furiosus
Extremophiles, 2006Co-Authors: Jana Tatur, Marieke L. Overeijnder, Peter-leon Hagedoorn, Wilfred R. HagenAbstract:A ferritin from the obligate anaerobe and hyperthermophilic archaeon Pyrococcus furiosus (optimal growth at 100°C) has been cloned and overproduced in Escherichia coli to one-fourth of total cell-free extract protein, and has been purified in one step to homogeneity. The ferritin (PfFtn) is structurally similar to known bacterial and eukaryal ferritins; it is a 24-mer of 20 kDa subunits, which add up to a total Mr 480 kDa. The protein belongs to the non-heme type of ferritins. The 24-mer contains approximately 17 Fe (as isolated), 2,700 Fe (fully loaded), or
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Pyrococcus furiosus ferredoxin is a functional dimer.
FEBS Letters, 2002Co-Authors: M.n Hasan, Peter-leon Hagedoorn, Wilfred R. HagenAbstract:Pyrococcus furiosus ferredoxin is subject to a monomer/dimer equilibrium as a function of ionic strength. At physiological ionic strength, approximately 0.35 M NaCl, the protein is very predominantly homodimer. The monomeric form exhibits impaired electron transfer on glassy carbon; it also has a decreased S=3/2 over S=1/2 ratio as shown by electron paramagnetic resonance spectroscopy. Even following sterilization at 121°C the dimer is stable in denaturing gel electrophoresis.
Sp Cramer - One of the best experts on this subject based on the ideXlab platform.
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l edge x ray absorption spectroscopy of Pyrococcus furiosus rubredoxin
Journal of the American Chemical Society, 1992Co-Authors: Sj George, J Vanelp, Jb Park, B G Searle, Fmf Degroot, J. C. Fuggle, Michael W W Adams, C.-t. Chen, Sp CramerAbstract:X-ray absorption spectroscopy has been used to probe the frozen solution structure of the metal site in Pyrococcus furiosus rubredoxin in the native, iron-containing protein and in zinc- and mercury-substituted proteins. For all samples studied, the spectra have been interpreted in terms of a single shell of coordinated sulfur, with approximately tetrahedral coordination. For the native protein we obtain Fe-S bond-lengths of 2.29 and 2.33 A for oxidized and reduced proteins, respectively. These values are in excellent agreement with those previously obtained from X-ray crystallography. The metal-substituted rubredoxins possess metal-sulfur bond lengths of 2.34 and 2.54 A for the zinc- and mercury-substituted proteins, respectively.
Sj George - One of the best experts on this subject based on the ideXlab platform.
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l edge x ray absorption spectroscopy of Pyrococcus furiosus rubredoxin
Journal of the American Chemical Society, 1992Co-Authors: Sj George, J Vanelp, Jb Park, B G Searle, Fmf Degroot, J. C. Fuggle, Michael W W Adams, C.-t. Chen, Sp CramerAbstract:X-ray absorption spectroscopy has been used to probe the frozen solution structure of the metal site in Pyrococcus furiosus rubredoxin in the native, iron-containing protein and in zinc- and mercury-substituted proteins. For all samples studied, the spectra have been interpreted in terms of a single shell of coordinated sulfur, with approximately tetrahedral coordination. For the native protein we obtain Fe-S bond-lengths of 2.29 and 2.33 A for oxidized and reduced proteins, respectively. These values are in excellent agreement with those previously obtained from X-ray crystallography. The metal-substituted rubredoxins possess metal-sulfur bond lengths of 2.34 and 2.54 A for the zinc- and mercury-substituted proteins, respectively.
Francis E. Jenney - One of the best experts on this subject based on the ideXlab platform.
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normal mode analysis of Pyrococcus furiosus rubredoxin via nuclear resonance vibrational spectroscopy nrvs and resonance raman spectroscopy
Journal of the American Chemical Society, 2005Co-Authors: Yuming Xiao, Francis E. Jenney, Michael W W Adams, Hongxin Wang, Simon J George, Matt C Smith, W Sturhahn, Jiyong Zhao, Yoshitaka Yoda, Edward I SolomonAbstract:We have used 57Fe nuclear resonance vibrational spectroscopy (NRVS) to study the Fe(Scys)4 site in reduced and oxidized rubredoxin (Rd) from Pyrococcus furiosus (Pf). The oxidized form has also bee...
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5 rubredoxin from Pyrococcus furiosus
Methods in Enzymology, 2001Co-Authors: Francis E. Jenney, Michael W W AdamsAbstract:Publisher Summary Rubredoxins are small, redox-active proteins that range in size from 45 to 55 amino acids. More than a dozen rubredoxins have been purified and characterized and the protein and complete genome databases contain 26 rubredoxinlike sequences. So far, rubredoxin has been found exclusively in strict anaerobes, which includes both bacteria and archaea, and some organisms that might be considered microaerophiles. There are a number of much larger proteins that contain rubredoxin-like sequences or domains and are found in facultative anaerobes and aerobes. Such proteins vary considerably in size of, as well as location of and distance between, the cysteine motifs. The canonical rubredoxin has been purified from only one hyperthermophile, the archaeon Pyrococcus furiosus . This chapter describes the purification of rubredoxin from P. furiosus and of the recombinant protein from Escherichia coli . Included are methods to obtain the 15 N-labeled form, which is very useful for detailed structural and dynamic analyses using NMR spectroscopy.
