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Kohtaro Kirimura - One of the best experts on this subject based on the ideXlab platform.
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Constitutive production of aconitate isomerase by Pseudomonas sp. WU-0701 in relation to trans-Aconitic Acid assimilation.
Journal of bioscience and bioengineering, 2020Co-Authors: Arisa Takiguchi, Isato Yoshioka, Yunosuke Oda, Yoshitaka Ishii, Kohtaro KirimuraAbstract:Aconitic Acid, an unsaturated tricarboxylic Acid, is used in the chemical industry as raw materials for organic synthesis, especially as a specific substrate for a flavoring agent. trans-Aconitic Acid (tAA) is a trans-isomer of cis-Aconitic Acid and detected in some plants and bacteria. However, biosynthetic route and metabolism of tAA in relation to assimilation have been unknown. Aconitate isomerase (AI; EC 5.3.3.7) catalyzes the reversible isomerization between cis-Aconitic Acid and tAA. Pseudomonas sp. WU-0701 was isolated as a bacterium assimilating tAA as sole carbon source, and characterization and gene identification of AI were already reported. Here, we describe that Pseudomonas sp. WU-0701 exhibited growth in each synthetic medium containing glucose, citric Acid, isocitric Acid, or tAA as sole carbon source. AI was intracellularly detected all the time during the cultivation of the strain WU-0701 cells, irrespective of the carbon sources; AI activity was detected even in the glucose-grown cells. Through the subcellular fractionation experiments, AI was detected in the periplasmic fraction. This is the first report indicating that a bacterium belonging to the genus Pseudomonas is constitutive for the AI production.
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Bioproduction of trans‐Aconitic Acid from Citric Acid by Whole‐Cell Reaction of Escherichia coli Heterologously Expressing the Aconitate Isomerase Gene from Pseudomonas sp. WU‐0701
ChemistrySelect, 2016Co-Authors: Keiichi Kobayashi, Junya Maruebi, Kohtaro KirimuraAbstract:Aconitate isomerase (AI; EC 5.3.3.7) catalyzes the isomerization of cis-Aconitic Acid and trans-Aconitic Acid. Since trans-Aconitic Acid is an unsaturated organic Acid, effective and environmentally benign processes are needed for trans-Aconitic Acid production. Here, the genes encoding AI from Pseudomonas sp. WU-0701 and aconitate hydratase (AH; EC 4.2.1.3) from Escherichia coli W3110, catalyzing the dehydration of citric Acid and formation of cis-Aconitic Acid, were co-expressed in E. coli Rosetta 2(DE3). The recombinant E. coli cells were used as biocatalysts for trans-Aconitic Acid production from citric Acid by whole-cell reaction. The optimal conditions were 37°C and pH 7.0. Using recombinant E. coli cells as biocatalysts for the whole-cell reaction, 91 mM trans-Aconitic Acid was produced from 400 mM citric Acid within 120 min. This is the first report describing a solvent- and harmful reagent-free system for trans-Aconitic Acid bioproduction usable under moderate conditions.
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bioproduction of trans Aconitic Acid from citric Acid by whole cell reaction of escherichia coli heterologously expressing the aconitate isomerase gene from pseudomonas sp wu 0701
ChemistrySelect, 2016Co-Authors: Keiichi Kobayashi, Junya Maruebi, Kohtaro KirimuraAbstract:Aconitate isomerase (AI; EC 5.3.3.7) catalyzes the isomerization of cis-Aconitic Acid and trans-Aconitic Acid. Since trans-Aconitic Acid is an unsaturated organic Acid, effective and environmentally benign processes are needed for trans-Aconitic Acid production. Here, the genes encoding AI from Pseudomonas sp. WU-0701 and aconitate hydratase (AH; EC 4.2.1.3) from Escherichia coli W3110, catalyzing the dehydration of citric Acid and formation of cis-Aconitic Acid, were co-expressed in E. coli Rosetta 2(DE3). The recombinant E. coli cells were used as biocatalysts for trans-Aconitic Acid production from citric Acid by whole-cell reaction. The optimal conditions were 37°C and pH 7.0. Using recombinant E. coli cells as biocatalysts for the whole-cell reaction, 91 mM trans-Aconitic Acid was produced from 400 mM citric Acid within 120 min. This is the first report describing a solvent- and harmful reagent-free system for trans-Aconitic Acid bioproduction usable under moderate conditions.
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Enzymatic characterization and gene identification of aconitate isomerase, an enzyme involved in assimilation of trans-Aconitic Acid, from Pseudomonas sp. WU-0701.
The FEBS journal, 2015Co-Authors: Kahori Yuhara, Keiichi Kobayashi, Hiromi Yonehara, Takasumi Hattori, Kohtaro KirimuraAbstract:UNLABELLED trans-Aconitic Acid is an unsaturated organic Acid that is present in some plants such as soybean and wheat; however, it remains unclear how trans-Aconitic Acid is degraded and/or assimilated by living cells in nature. From soil, we isolated Pseudomonas sp. WU-0701 assimilating trans-Aconitic Acid as a sole carbon source. In the cell-free extract of Pseudomonas sp. WU-0701, aconitate isomerase (AI; EC 5.3.3.7) activity was detected. Therefore, it seems likely that strain Pseudomonas sp. WU-0701 converts trans-Aconitic Acid to cis-Aconitic Acid with AI, and assimilates this via the tricarboxylic Acid cycle. For the characterization of AI from Pseudomonas sp. WU-0701, we performed purification, determination of enzymatic properties and gene identification of AI. The molecular mass of AI purified from cell-free extract was estimated to be ~ 25 kDa by both SDS/PAGE and gel filtration analyses, indicating that AI is a monomeric enzyme. The optimal pH and temperature of purified AI for the reaction were 6.0 °C and 37 °C, respectively. The gene ais encoding AI was cloned on the basis of the N-terminal amino Acid sequence of the protein, and Southern blot analysis revealed that only one copy of ais is located on the bacterial genome. The gene ais contains an ORF of 786 bp, encoding a polypeptide of 262 amino Acids, including the N-terminal 22 amino Acids as a putative periplasm-targeting signal peptide. It is noteworthy that the amino Acid sequence of AI shows 90% and 74% identity with molybdenum ABC transporter substrate-binding proteins of Pseudomonas psychrotolerans and Xanthomonas albilineans, respectively. This is the first report on purification to homogeneity, characterization and gene identification of AI. DATABASE The nucleotide sequence of ais described in this article is available in the DDBJ/EMBL/GenBank nucleotide sequence databases under the Accession No. LC010980.
Horacio N. Sólimo - One of the best experts on this subject based on the ideXlab platform.
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aqueous phase diagrams containing t Aconitic Acid 1 pentanol or isobutyl acetate or methyl isobutyl ketone at 303 15 k
Fluid Phase Equilibria, 2000Co-Authors: Norma Barnes, Mónica B. Gramajo De Doz, Horacio N. SólimoAbstract:Abstract Phase diagrams of ternary systems, water+ t -Aconitic Acid (AA)+(1-pentanol (P) or +isobutyl acetate (iBuAc) or +methyl isobutyl ketone (MIK)), were obtained at 303.15±0.05 K. Experimental results show that all aqueous AA systems have one liquid–liquid equilibria region and three solid–liquid equilibria zones, where the solid is the AA. The recovery of this Acid from aqueous solutions was evaluated by analyzing its distribution coefficients, selectivities, and distribution curves on a solvent-free basis. Although the experimental distribution coefficients are practically always less than unity for the three systems, the selectivities are higher due to the lower solubility of the non-consolutes, particularly for MIK, which appears as the best solvent among those studied here. The experimental data were also compared with values calculated by the NRTL and UNIQUAC equations for these ternary mixtures.
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Liquid-liquid extraction of trans-Aconitic Acid from aqueous solutions with tributyl phosphate and a mixed solvent at 303.15 K
Industrial & Engineering Chemistry Research, 2000Co-Authors: Norma Barnes, M. B. Gramajo De Doz, Horacio N. SólimoAbstract:The phase diagram of the water + trans-Aconitic Acid + tributyl phosphate ternary system was obtained at 303.15 K. Experiments were also conducted on the equilibrium distribution of trans-Aconitic Acid between its aqueous solutions and a mixed solvent: tributyl phosphate (TBP) + hexane (H) (with a volume ratio of 60/40 TBP/H). Analysis of the results shows that the diluent (H) decreases the selectivity and the distribution coefficient when compared with pure TBP. However, this is not relevant because these properties are still appropriate for extraction purposes. Additionally, a multistage cross-flow extraction process was performed in order to verify the accuracy of the basic equilibrium data and to obtain the number of stages required to extract trans-Aconitic Acid from its aqueous solutions. This number was also graphically determined by using a distribution diagram in Bancroft's coordinates and analytically calculated assuming virtual immiscibility between the feed and the extraction solvents. The extraction process was also simulated following the procedure contained in the ChemCAD Process Flowsheet Simulator 4.0 and compared with the experimental results.
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Aqueous phase diagrams containing t-Aconitic Acid+(1-pentanol or +isobutyl acetate or +methyl isobutyl ketone) at 303.15 K☆
Fluid Phase Equilibria, 2000Co-Authors: Norma Barnes, Mónica B. Gramajo De Doz, Horacio N. SólimoAbstract:Abstract Phase diagrams of ternary systems, water+ t -Aconitic Acid (AA)+(1-pentanol (P) or +isobutyl acetate (iBuAc) or +methyl isobutyl ketone (MIK)), were obtained at 303.15±0.05 K. Experimental results show that all aqueous AA systems have one liquid–liquid equilibria region and three solid–liquid equilibria zones, where the solid is the AA. The recovery of this Acid from aqueous solutions was evaluated by analyzing its distribution coefficients, selectivities, and distribution curves on a solvent-free basis. Although the experimental distribution coefficients are practically always less than unity for the three systems, the selectivities are higher due to the lower solubility of the non-consolutes, particularly for MIK, which appears as the best solvent among those studied here. The experimental data were also compared with values calculated by the NRTL and UNIQUAC equations for these ternary mixtures.
Arisa Takiguchi - One of the best experts on this subject based on the ideXlab platform.
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Constitutive production of aconitate isomerase by Pseudomonas sp. WU-0701 in relation to trans-Aconitic Acid assimilation.
Journal of bioscience and bioengineering, 2020Co-Authors: Arisa Takiguchi, Isato Yoshioka, Yunosuke Oda, Yoshitaka Ishii, Kohtaro KirimuraAbstract:Aconitic Acid, an unsaturated tricarboxylic Acid, is used in the chemical industry as raw materials for organic synthesis, especially as a specific substrate for a flavoring agent. trans-Aconitic Acid (tAA) is a trans-isomer of cis-Aconitic Acid and detected in some plants and bacteria. However, biosynthetic route and metabolism of tAA in relation to assimilation have been unknown. Aconitate isomerase (AI; EC 5.3.3.7) catalyzes the reversible isomerization between cis-Aconitic Acid and tAA. Pseudomonas sp. WU-0701 was isolated as a bacterium assimilating tAA as sole carbon source, and characterization and gene identification of AI were already reported. Here, we describe that Pseudomonas sp. WU-0701 exhibited growth in each synthetic medium containing glucose, citric Acid, isocitric Acid, or tAA as sole carbon source. AI was intracellularly detected all the time during the cultivation of the strain WU-0701 cells, irrespective of the carbon sources; AI activity was detected even in the glucose-grown cells. Through the subcellular fractionation experiments, AI was detected in the periplasmic fraction. This is the first report indicating that a bacterium belonging to the genus Pseudomonas is constitutive for the AI production.
Olga Izquierdo - One of the best experts on this subject based on the ideXlab platform.
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Quantitation of trans-Aconitic Acid in Different Stages of the Sugar-Manufacturing Process
Journal of agricultural and food chemistry, 2014Co-Authors: Guillermo Montoya, July Londono, Paola Cortes, Olga IzquierdoAbstract:The sugar cane industry has seen how biomass production in sugar mills would be converted to a readily available source of molecules besides sugar. Properly managed, byproducts would be transformed into a sustainable source of renewable and environmentally friendly chemical products. As a principal and more abundant organic Acid in sugar cane juice, trans-Aconitic Acid (TAA) has been studied for use as a plasticizer in the polymer industry. However, up to now no industrial-scale application has been reported. As a reasonable approach to recover TAA from a sugar mill, first, an analytical method to determine its presence in all stages of the sugar-manufacturing process is needed. A new modern method was developed to measure TAA in seven stages in a sugar mill located in Valle del Cauca, Colombia. The stages with higher content of TAA were syrup, with 3363.6 ± 589.3 mg/L, and honey (molasses), with 6110.05 ± 139.5 mg/L.
Akanksha Kanitkar - One of the best experts on this subject based on the ideXlab platform.
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Original Manuscript
2016Co-Authors: Akanksha Kanitkar, Cong Chen, Katie Hogan, Mollie Smoak, Thomas Scherr, Giovanna Aita, Daniel HayesAbstract:In vitro characterization of polyesters of Aconitic Acid, glycerol, and cinnamic Acid for bone tissue engineerin
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Hard Tissues and Materials In
2016Co-Authors: Akanksha Kanitkar, Cong Chen, Katie Hogan, Mollie Smoak, Thomas Scherr, Giovanna Aita, Daniel HayesAbstract:vitro characterization of polyesters of Aconitic Acid, glycerol, and cinnamic Acid for bone tissue engineerin
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In vitro characterization of polyesters of Aconitic Acid, glycerol, and cinnamic Acid for bone tissue engineering:
Journal of biomaterials applications, 2014Co-Authors: Akanksha Kanitkar, Giovanna M. Aita, Cong Chen, Mollie M. Smoak, Katie Hogan, Thomas F. Scherr, Daniel J. HayesAbstract:In this study, a novel class of polyesters of glycerol, Aconitic Acid, and cinnamic Acid were synthesized along with their hydroxyapatite (HA) composites, and studied for their potential application in bone defect repair. An osteogenic study was conducted with human adipose derived mesenchymal stem cells (hASCs) to determine the osteoinductive ability of Aconitic Acid-glycerol (AG) polyesters, AG:HA (80:20), Aconitic Acid-glycerol-cinnamic Acid (AGC) polyesters, and AGC:HA (80:20) to serve as bone scaffolds. The results indicate that AGC scaffolds have the highest mechanical strength in comparison to AG, AG:HA (80:20), and AGC:HA (80:20) scaffolds due to its low porosity. It was determined by cytotoxicity and osteogenesis experiments that hASCs cultured for 21 days on AG:HA (80:20) scaffolds in stromal medium exhibited a greater number of live cells than control PCL:HA composites. Moreover, hASCs cultured on foamed AG:HA (80:20) scaffolds resulted in the highest levels of mineralization, increased alkaline phosphatase (ALP) expression, and the greatest osteocalcin (OCN) expression after 21 days. Overall, AG:HA (100:0 and 80:20) scaffolds had higher mechanical strength and cytocompatibility than the PCL:HA control. In vitro osteogenic study demonstrated that AG:HA (100:0 and 80:20) synthesized using sugarcane industry by-products hold potential as scaffolds for bone tissue engineering applications.
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The recovery of polymerization grade Aconitic Acid from sugarcane molasses
Journal of Chemical Technology & Biotechnology, 2013Co-Authors: Akanksha Kanitkar, Giovanna M. Aita, Lee MadsenAbstract:BACKGROUND Aconitic Acid (propene-1, 2, 3- tricarboxylic Acid) is the most prevalent organic Acid found in sugar cane. It is used in the food processing industry as an Acidulant and can be used in the synthesis of plasticizers. It can also be used to synthesize biodegradable polyesters for tissue engineering applications. In this study, Aconitic Acid was isolated from sugarcane molasses via liquid–liquid extraction with ethyl acetate. Six combinations of time and temperature (1–6 h at either 30 or 40°C) were tested. In order to conserve solvent, ethyl acetate was recovered and reused for subsequent extractions. The recovery of Aconitic Acid from vinasse was also evaluated. RESULTS Under the most efficient set of conditions, 69% of the Aconitic Acid was recovered as free Acid. The purity (HPLC) of the extracted Acid was found to be 99.9%. Ethanol was an additional stream that was generated by fermentation of molasses and yields of 12.4% (g per 100 g of molasses) were obtained. CONCLUSION The yield of Aconitic Acid from molasses varied from 34–69%, depending on the extraction conditions, with purity of the extracted Acid being 99.9%. The Aconitic Acid is of a quality sufficient to synthesize polymers that could realize high-value in biomedical applications. © 2013 Society of Chemical Industry
