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Makoto Shoda - One of the best experts on this subject based on the ideXlab platform.
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treatment of municipal landfill leachate at different stabilization stages in two stage membrane bioreactor bioaugmented with Alcaligenes faecalis no 4
Bioresource Technology Reports, 2020Co-Authors: Ngech Horng Heang, Wilai Chiemchaisri, Chart Chiemchaisri, Makoto ShodaAbstract:Abstract Organic and nitrogen removals in two-stage membrane bioreactor (2-stage MBR) applied to the treatment of fresh, mixed, and partially stabilized leachate at different concentrations were investigated. A pilot-scale 2-stage MBR system was operated at a different hydraulic retention time of 2.5 and 1 days during which organic loading rates were varied between 1.5 and 20.2 kg BOD/m3 d. The effect of Alcaligenes faecalis no.4 bio-augmentation and its survival during the treatment was examined. High organic and nitrogen removals (>90%) was achieved when the system was applied to fresh and mixed leachate with BOD/COD of 0.5–0.76 but the removals of COD, TKN was reduced to 58–70% and A. faecalis no.4 population became extinct when partially stabilized leachate was pre-treated and reduced its BOD/COD to 0.11. This study demonstrates the applicability of 2-stage MBR to the treatment of leachate with varied characteristics provided that its treatment conditions were properly adjusted.
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treatment of concentrated leachate with low greenhouse gas emission in two stage membrane bioreactor bio augmented with Alcaligenes faecalis no 4
Journal of The Air & Waste Management Association, 2018Co-Authors: Nararatchporn Nuansawan, Chart Chiemchaisri, Wilai Chiemchaisri, Makoto ShodaAbstract:Methane (CH4) and nitrous oxide (N2O) emissions from two-stage membrane bioreactor (MBR) bio-augmented by Alcaligenes faecalis no. 4 during municipal solid waste leachate treatment were investigate...
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heterotrophic nitrification and aerobic denitrification of high strength ammonium in anaerobically digested sludge by Alcaligenes faecalis strain no 4
Journal of Bioscience and Bioengineering, 2014Co-Authors: Makoto Shoda, Yoichi IshikawaAbstract:Alcaligenes faecalis strain No. 4 which is capable of heterogeneous nitrification and aerobic denitrification, was used to remove high-strength ammonium (approximately 1 g NH 4 + -N/l) from digested sludge, the product of an anaerobic digestion reactor, in which methane was produced from excess municipal sewage sludge. Repeated batch operations were conducted at 20°C and 30°C for 550 h, using a jar fermentor. The removal ratios of high-strength ammonium reached 90–100% within 24 h, and the average ammonium removal rate was 2.9 kg-N/m3/day, more than 200 times higher than that in conventional nitrification–denitrification processes. During these operations, the cell density was maintained at 108–109 cells of A. faecalis strain No. 4/ml. At 3% NaCl in the digested sludge, strain No. 4 exhibited an ammonium removal rate of 3 kg-N/m3/day.
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improvement in ammonium removal efficiency in wastewater treatment by mixed culture of Alcaligenes faecalis no 4 and l1
Journal of Bioscience and Bioengineering, 2007Co-Authors: Mitsuyo Hirai, Makoto ShodaAbstract:To improve ammonium removal efficiency in wastewater treatment, a mixed culture of Alcaligenes faecalis no. 4 and its mutant L1, both of which have heterotrophic nitrification and aerobic denitrification abilities, was performed. In a batch culture, no. 4 has a higher denitrification ability than L1, but its ammonium removal rate was lower. In a mixed continuous culture in the ammonium loading range of 750 to 3500 mg-N/l/d, the average ammonium removal rate and the average denitrification ratio were 61 mg-N/l/h and 31%, respectively. In the mixed culture, the ammonium removal rate was twofold higher than that in a single culture of no. 4, the rate was similar to that in a single culture of L1, and the denitrification ratio was very high compared with that in the single culture of L1.
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piggery wastewater treatment using Alcaligenes faecalis strain no 4 with heterotrophic nitrification and aerobic denitrification
Water Research, 2006Co-Authors: Mitsuyo Hirai, Makoto ShodaAbstract:Abstract Alcaligenes faecalis strain No. 4, which has heterotrophic nitrification and aerobic denitrification abilities, was used to treat actual piggery wastewater containing high-strength ammonium under aerobic conditions. In a continuous experiment using a solids-free wastewater (SFW) mixed with feces, almost all of the 2000 NH 4 + –N mg/L and 12,000 COD mg/L in the wastewater was removed and the ammonium removal rate was approximately 30 mg–N/L/h, which was 5–10 times higher than the rates achieved by other bacteria with the same abilities. The denitrification ratio was more than 65% of removed NH 4 + –N, indicating that strain No. 4 exhibited its heterotrophic nitrification and aerobic denitrification abilities in the piggery wastewater.
Elinor T Adman - One of the best experts on this subject based on the ideXlab platform.
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structure of nitrite bound to copper containing nitrite reductase from Alcaligenes faecalis mechanistic implications
Journal of Biological Chemistry, 1997Co-Authors: Michael E P Murphy, S Turley, Elinor T AdmanAbstract:Abstract The structures of oxidized, reduced, nitrite-soaked oxidized and nitrite-soaked reduced nitrite reductase from Alcaligenes faecalis have been determined at 1.8–2.0 A resolution using data collected at −160 °C. The active site at cryogenic temperature, as at room temperature, contains a tetrahedral type II copper site liganded by three histidines and a water molecule. The solvent site is empty when crystals are reduced with ascorbate. A fully occupied oxygen-coordinate nitrite occupies the solvent site in crystals soaked in nitrite. Ascorbate-reduced crystals soaked in a glycerol-methanol solution and nitrite at −40 °C remain colorless at −160 °C but turn amber-brown when warmed, suggesting that NO is released. Nitrite is found at one-half occupancy. Five new solvent sites in the oxidized nitrite bound form exhibit defined but different occupancies in the other three forms. These results support a previously proposed mechanism by which nitrite is bound primarily by a single oxygen atom that is protonable, and after reduction and cleavage of that N–O bond, NO is released leaving the oxygen atom bound to the Cu site as hydroxide or water.
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structure of nitrite bound to copper containing nitrite reductase from Alcaligenes faecalis mechanistic implications
Journal of Biological Chemistry, 1997Co-Authors: Michael E P Murphy, S Turley, Elinor T AdmanAbstract:The structures of oxidized, reduced, nitrite-soaked oxidized and nitrite-soaked reduced nitrite reductase from Alcaligenes faecalis have been determined at 1.8-2.0 A resolution using data collected at -160 degrees C. The active site at cryogenic temperature, as at room temperature, contains a tetrahedral type II copper site liganded by three histidines and a water molecule. The solvent site is empty when crystals are reduced with ascorbate. A fully occupied oxygen-coordinate nitrite occupies the solvent site in crystals soaked in nitrite. Ascorbate-reduced crystals soaked in a glycerol-methanol solution and nitrite at -40 degrees C remain colorless at -160 degrees C but turn amber-brown when warmed, suggesting that NO is released. Nitrite is found at one-half occupancy. Five new solvent sites in the oxidized nitrite bound form exhibit defined but different occupancies in the other three forms. These results support a previously proposed mechanism by which nitrite is bound primarily by a single oxygen atom that is protonable, and after reduction and cleavage of that N-O bond, NO is released leaving the oxygen atom bound to the Cu site as hydroxide or water.
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studies on protein protein interaction between copper containing nitrite reductase and pseudoazurin from Alcaligenes faecalis s 6
Journal of Biological Chemistry, 1996Co-Authors: Mutsuko Kukimoto, Makoto Nishiyama, Elinor T Adman, Masaru Tanokura, Sueharu HorinouchiAbstract:Site-directed mutagenesis of a copper-containing nitrite reductase (NIR) from Alcaligenes faecalis S-6 was carried out to identify the amino acid residues involved in interaction with its redox partner, pseudoazurin, in which four positively charged residues were previously shown to be important in the interaction. Ten negatively charged residues located on the surface of NIR were replaced independently by alanine or serine. All the altered NIRs showed CD spectra and optical spectra identical to those of wild-type NIR, suggesting that all the replacements caused no gross change in the overall structure or in the environment of type 1 copper site. Kinetic analysis of electron transfer between pseudoazurin and altered NIRs revealed that the replacement of Glu-118, Glu-197, Asp-201, Glu-204, or Asp-205 by Ala caused a significant increase in the Km value for pseudoazurin compared with that of wild-type NIR. Furthermore, the simultaneous replacement of three of these residues (Glu-118, Glu-197, and Asp-201) caused a further increase in the Km value. These results suggested that the negatively charged residues are involved in electrostatic interaction with pseudoazurin. Kinetic analyses of the altered NIRs (E118A, E197A, or D201A) with altered pseudoazurins (K10A, K57A, or K77A) implicate specific pairs of the charged residues that are involved in electrostatic interaction between NIR and pseudoazurin.
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structure of Alcaligenes faecalis nitrite reductase and a copper site mutant m150e that contains zinc
Biochemistry, 1995Co-Authors: Michael E P Murphy, Makoto Nishiyama, Mutsuko Kukimoto, Sueharu Horinouchi, S Turley, Hiroshi Sasaki, Masaru Tanokura, Elinor T AdmanAbstract:The structures at 2.0 and 2.25 A resolution of native and recombinant nitrite reductase from Alcaligenes faecalis show that they are identical to each other and very similar to nitrite reductase from Achromobacter cycloclastes. The crystallographic structure of a mutant, M150E, which unlike the wild-type protein cannot be reduced by pseudoazurin, shows that the glutamate replacement for methionine binds to a metal at the type I Cu site via only one oxygen. Anomalous scattering data collected at wavelengths of 1.040 and 1.377 A reveal that the metal at the type I site is a Zn. No significant differences from the native structure other than local perturbations at the type I site are seen. A local pseudo 2-fold axis relates the two domains of different monomers which form the active site. The two residues, Asp98 and His255, believed to be involved in catalysis are related by this 2-fold. An unusual (+)-(+) charge interaction between Lys269, Glu279, and His100 helps to orient the active site Cu ligand, His100. A number of negatively charged surface residues create an electrostatic field whose shape suggests that it may serve to direct incoming negatively charged nitrite as well as to dock the electron donor partner, pseudoazurin.
Mitsuyo Hirai - One of the best experts on this subject based on the ideXlab platform.
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improvement in ammonium removal efficiency in wastewater treatment by mixed culture of Alcaligenes faecalis no 4 and l1
Journal of Bioscience and Bioengineering, 2007Co-Authors: Mitsuyo Hirai, Makoto ShodaAbstract:To improve ammonium removal efficiency in wastewater treatment, a mixed culture of Alcaligenes faecalis no. 4 and its mutant L1, both of which have heterotrophic nitrification and aerobic denitrification abilities, was performed. In a batch culture, no. 4 has a higher denitrification ability than L1, but its ammonium removal rate was lower. In a mixed continuous culture in the ammonium loading range of 750 to 3500 mg-N/l/d, the average ammonium removal rate and the average denitrification ratio were 61 mg-N/l/h and 31%, respectively. In the mixed culture, the ammonium removal rate was twofold higher than that in a single culture of no. 4, the rate was similar to that in a single culture of L1, and the denitrification ratio was very high compared with that in the single culture of L1.
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piggery wastewater treatment using Alcaligenes faecalis strain no 4 with heterotrophic nitrification and aerobic denitrification
Water Research, 2006Co-Authors: Mitsuyo Hirai, Makoto ShodaAbstract:Abstract Alcaligenes faecalis strain No. 4, which has heterotrophic nitrification and aerobic denitrification abilities, was used to treat actual piggery wastewater containing high-strength ammonium under aerobic conditions. In a continuous experiment using a solids-free wastewater (SFW) mixed with feces, almost all of the 2000 NH 4 + –N mg/L and 12,000 COD mg/L in the wastewater was removed and the ammonium removal rate was approximately 30 mg–N/L/h, which was 5–10 times higher than the rates achieved by other bacteria with the same abilities. The denitrification ratio was more than 65% of removed NH 4 + –N, indicating that strain No. 4 exhibited its heterotrophic nitrification and aerobic denitrification abilities in the piggery wastewater.
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characteristics of ammonium removal by heterotrophic nitrification aerobic denitrification by Alcaligenes faecalis no 4
Journal of Bioscience and Bioengineering, 2005Co-Authors: Mitsuyo Hirai, Makoto ShodaAbstract:Alcaligenes faecalis no. 4 has heterotrophic nitrification and aerobic denitrification abilities. By taking the nitrogen balance under different culture conditions, 40–50% of removed NH4+-N was denitrified and about one-half of removed NH4+-N was converted to intracellular nitrogen. The maximum ammonium removal rate of no. 4 (28.9 mg-N/l/h) and its denitrification rate at high-strength NH4+-N of about 1200 ppm in aerated batch experiments at a C/N ratio of 10 were 5–40 times higher than those of other bacteria with the same ability. Only a few percent of the removed ammonium was converted to nitrite, and the main denitrification process was speculated to be via hydroxylamine which was produced by ammonium oxidation.
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Nitrification and Denitrification in High-Strength Ammonium by Alcaligenes faecalis
Biotechnology Letters, 2005Co-Authors: Mitsuyo Hirai, Makoto ShodaAbstract:Alcaligenes faecalis sp. No. 4, that has the ability of heterotrophic nitrification and aerobic denitrification in high-strength ammonium at about 1200 mg-N/l, converted about one-half of removed NH _4 ^+ -N to intracellular nitrogen and nitrified only 3% of the removed NH _4 ^+ . From the nitrogen balance, 40–50% of removed NH _4 ^+ -N was estimated to be denitrified. Production of N_2 was confirmed by GC-MS and 90% of denitrified products was N_2. The maximum ammonium removal rate, 29 mg-N/l h and its denitrification rate in aerated batch experiments, were 5–40 times higher than those of other bacteria with the same ability.
Dieter Jendrossek - One of the best experts on this subject based on the ideXlab platform.
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Determination of the active sites serine of the poly (3-hydroxybutyrate) depolymerases of Pseudomonas lemoignei (PhaZ5) and of Alcaligenes faecalis
FEMS microbiology letters, 1996Co-Authors: Takeyuki Shinohe, Terumi Saito, Masaki Nojiri, Thomas Stanislawski, Dieter JendrossekAbstract:Mutational analysis of the poly(3-hydroxybutyrate) (PHB) depolymerase A of Pseudomonas lemoignei and of the poly(3-hydroxybutyrate) depolymerase of Alcaligenes faecalis revealed that S138 ( P. lemoignei) and S139 ( A. faecalis) are essential for activity. Both serines are part of a strictly conserved pentapeptide sequence which is present in all poly(3-hydroxybutyrate) depolymerases analyzed so far (G-L-S-S(A)-G) and which resembles the lipase ☐ of lipases and other serine hydrolases (G-X-S-X-G). Mutation of another conserved serine, namely S195 ( P. lemoignei) and S196 ( A. faecalis), resulted in mutant proteinswith almost full activity and proved that S195 and S196 are not essential for activity. The results indicate the structural and functional relationship of poly(3-hydroxybutyrate) depolymerases to the family of serine hydrolases.
Michael E P Murphy - One of the best experts on this subject based on the ideXlab platform.
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a single crystal epr study at 95 ghz of the type 2 copper site of nitrite reductase from Alcaligenes faecalis
Applied Magnetic Resonance, 2015Co-Authors: Francesco Scarpelli, Angele L Arrieta, Peter Gast, Edgar J J Groenen, S Milikisyants, Michael E P Murphy, Martina HuberAbstract:An electron spin echo-detected electron paramagnetic resonance study has been performed on the type-2 copper site of the nitrite reductase from Alcaligenes faecalis. The experiment on a single crystal at 95 GHz has allowed the determination of the complete g tensor. This includes the orientations of the principal axes of three g tensors in the asymmetric unit of the unit cell with respect to the crystallographic axes. The orientation with respect to the crystallographic axes has been translated into the orientation of the g tensor in the type-2 copper site. The corresponding electronic structure is discussed in relation to the enzymatic function of this copper site.
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structure of nitrite bound to copper containing nitrite reductase from Alcaligenes faecalis mechanistic implications
Journal of Biological Chemistry, 1997Co-Authors: Michael E P Murphy, S Turley, Elinor T AdmanAbstract:Abstract The structures of oxidized, reduced, nitrite-soaked oxidized and nitrite-soaked reduced nitrite reductase from Alcaligenes faecalis have been determined at 1.8–2.0 A resolution using data collected at −160 °C. The active site at cryogenic temperature, as at room temperature, contains a tetrahedral type II copper site liganded by three histidines and a water molecule. The solvent site is empty when crystals are reduced with ascorbate. A fully occupied oxygen-coordinate nitrite occupies the solvent site in crystals soaked in nitrite. Ascorbate-reduced crystals soaked in a glycerol-methanol solution and nitrite at −40 °C remain colorless at −160 °C but turn amber-brown when warmed, suggesting that NO is released. Nitrite is found at one-half occupancy. Five new solvent sites in the oxidized nitrite bound form exhibit defined but different occupancies in the other three forms. These results support a previously proposed mechanism by which nitrite is bound primarily by a single oxygen atom that is protonable, and after reduction and cleavage of that N–O bond, NO is released leaving the oxygen atom bound to the Cu site as hydroxide or water.
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structure of nitrite bound to copper containing nitrite reductase from Alcaligenes faecalis mechanistic implications
Journal of Biological Chemistry, 1997Co-Authors: Michael E P Murphy, S Turley, Elinor T AdmanAbstract:The structures of oxidized, reduced, nitrite-soaked oxidized and nitrite-soaked reduced nitrite reductase from Alcaligenes faecalis have been determined at 1.8-2.0 A resolution using data collected at -160 degrees C. The active site at cryogenic temperature, as at room temperature, contains a tetrahedral type II copper site liganded by three histidines and a water molecule. The solvent site is empty when crystals are reduced with ascorbate. A fully occupied oxygen-coordinate nitrite occupies the solvent site in crystals soaked in nitrite. Ascorbate-reduced crystals soaked in a glycerol-methanol solution and nitrite at -40 degrees C remain colorless at -160 degrees C but turn amber-brown when warmed, suggesting that NO is released. Nitrite is found at one-half occupancy. Five new solvent sites in the oxidized nitrite bound form exhibit defined but different occupancies in the other three forms. These results support a previously proposed mechanism by which nitrite is bound primarily by a single oxygen atom that is protonable, and after reduction and cleavage of that N-O bond, NO is released leaving the oxygen atom bound to the Cu site as hydroxide or water.
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structure of Alcaligenes faecalis nitrite reductase and a copper site mutant m150e that contains zinc
Biochemistry, 1995Co-Authors: Michael E P Murphy, Makoto Nishiyama, Mutsuko Kukimoto, Sueharu Horinouchi, S Turley, Hiroshi Sasaki, Masaru Tanokura, Elinor T AdmanAbstract:The structures at 2.0 and 2.25 A resolution of native and recombinant nitrite reductase from Alcaligenes faecalis show that they are identical to each other and very similar to nitrite reductase from Achromobacter cycloclastes. The crystallographic structure of a mutant, M150E, which unlike the wild-type protein cannot be reduced by pseudoazurin, shows that the glutamate replacement for methionine binds to a metal at the type I Cu site via only one oxygen. Anomalous scattering data collected at wavelengths of 1.040 and 1.377 A reveal that the metal at the type I site is a Zn. No significant differences from the native structure other than local perturbations at the type I site are seen. A local pseudo 2-fold axis relates the two domains of different monomers which form the active site. The two residues, Asp98 and His255, believed to be involved in catalysis are related by this 2-fold. An unusual (+)-(+) charge interaction between Lys269, Glu279, and His100 helps to orient the active site Cu ligand, His100. A number of negatively charged surface residues create an electrostatic field whose shape suggests that it may serve to direct incoming negatively charged nitrite as well as to dock the electron donor partner, pseudoazurin.