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A H Goldstein - One of the best experts on this subject based on the ideXlab platform.
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cloning of an erwinia herbicola gene necessary for Gluconic Acid production and enhanced mineral phosphate solubilization in escherichia coli hb101 nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone
Journal of Bacteriology, 1992Co-Authors: Shihtung Liu, Lanying Lee, Chinying Tai, Chienhui Hung, Yusun Chang, J H Wolfram, R Rogers, A H GoldsteinAbstract:Escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (GDH) but not the cofactor pyrroloquinoline quinone (PQQ), which is essential for formation of the holoenzyme. Therefore, in the absence of exogenous PQQ, E. coli does not produce Gluconic Acid. Evidence is presented to show that the expression of an Erwinia herbicola gene in E. coli HB101(pMCG898) resulted in the production of Gluconic Acid, which, in turn, implied PQQ biosynthesis. Transposon mutagenesis showed that the essential gene or locus was within a 1.8-kb region of a 4.5-kb insert of the plasmid pMCG898. This 1.8-kb region contained only one apparent open reading frame. In this paper, we present the nucleotide sequence of this open reading frame, a 1,134-bp DNA fragment coding for a protein with an M(r) of 42,160. The deduced sequence of this protein had a high degree of homology with that of gene III (M(r), 43,600) of a PQQ synthase gene complex from Acinetobacter calcoaceticus previously identified by Goosen et al. (J. Bacteriol. 171:447-455, 1989). In minicell analysis, pMCG898 encoded a protein with an M(r) of 41,000. These data indicate that E. coli HB101(pMCG898) produced the GDH-PQQ holoenzyme, which, in turn, catalyzed the oxidation of glucose to Gluconic Acid in the periplasmic space. As a result of the Gluconic Acid production, E. coli HB101(pMCG898) showed an enhanced mineral phosphate-solubilizing phenotype due to Acid dissolution of the hydroxyapatite substrate.
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cloning of an erwinia herbicola gene necessary for Gluconic Acid production and enhanced mineral phosphate solubilization in escherichia coli hb101 nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone
Journal of Bacteriology, 1992Co-Authors: Shihtung Liu, Lanying Lee, Chinying Tai, Chienhui Hung, Yusun Chang, J H Wolfram, R Rogers, A H GoldsteinAbstract:Escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (GDH) but not the cofactor pyrroloquinoline quinone (PQQ), which is essential for formation of the holoenzyme. Therefore, in the absence of exogenous PQQ, E. coli does not produce Gluconic Acid. Evidence is presented to show that the expression of an Erwinia herbicola gene in E. coli HB101(pMCG898) resulted in the production of Gluconic Acid, which, in turn, implied PQQ biosynthesis. Transposon mutagenesis showed that the essential gene or locus was within a 1.8-kb region of a 4.5-kb insert of the plasmid pMCG898. This 1.8-kb region contained only one apparent open reading frame. In this paper, we present the nucleotide sequence of this open reading frame, a 1,134-bp DNA fragment coding for a protein with an M(r) of 42,160. The deduced sequence of this protein had a high degree of homology with that of gene III (M(r), 43,600) of a PQQ synthase gene complex from Acinetobacter calcoaceticus previously identified by Goosen et al. (J. Bacteriol. 171:447-455, 1989). In minicell analysis, pMCG898 encoded a protein with an M(r) of 41,000. These data indicate that E. coli HB101(pMCG898) produced the GDH-PQQ holoenzyme, which, in turn, catalyzed the oxidation of glucose to Gluconic Acid in the periplasmic space. As a result of the Gluconic Acid production, E. coli HB101(pMCG898) showed an enhanced mineral phosphate-solubilizing phenotype due to Acid dissolution of the hydroxyapatite substrate. Images
Hongdan Zhang - One of the best experts on this subject based on the ideXlab platform.
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direct transformation of cellulose to Gluconic Acid in a concentrated iron iii chloride solution under mild conditions
ACS Sustainable Chemistry & Engineering, 2017Co-Authors: Hongdan Zhang, Xuejun Pan, Jun XieAbstract:A simple method for directly converting cellulose to Gluconic Acid in a concentrated iron(III) chloride (FeCl3) solution without an additional catalyst was demonstrated. It was found that the conversion of cellulose to Gluconic Acid in FeCl3 is a two-step process, fast hydrolysis of cellulose to glucose followed by slow oxidation of glucose to Gluconic Acid. It was confirmed that high-concentration FeCl3 (60%) is required to efficiently dissolve and subsequently hydrolyze cellulose. The sequential combination of 60 and 40% FeCl3 in two steps was optimal for converting cellulose to Gluconic Acid, and 40% FeCl3 in the second step could minimize the oxidative decomposition of Gluconic Acid. The results indicated that the maximal Gluconic Acid yield (50%) was achieved after hydrolysis for 10 min in 60% FeCl3 followed by oxidation for 110 min in 40% FeCl3 at 120 °C. The system presented in this study provides a new approach to producing Gluconic Acid directly from cellulose.
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oxidative conversion of glucose to Gluconic Acid by iron iii chloride in water under mild conditions
Green Chemistry, 2016Co-Authors: Hongdan Zhang, Xuejun Pan, Jun XieAbstract:A simple method was demonstrated to oxidize glucose into Gluconic Acid in a concentrated FeCl3 solution. The maximum Gluconic Acid yield (52.3%) was achieved in the 40% FeCl3 solution at 110 °C in 4 hours. Formic and acetic Acids were the main coproducts with an yield of 10–20%.
Shihtung Liu - One of the best experts on this subject based on the ideXlab platform.
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cloning of an erwinia herbicola gene necessary for Gluconic Acid production and enhanced mineral phosphate solubilization in escherichia coli hb101 nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone
Journal of Bacteriology, 1992Co-Authors: Shihtung Liu, Lanying Lee, Chinying Tai, Chienhui Hung, Yusun Chang, J H Wolfram, R Rogers, A H GoldsteinAbstract:Escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (GDH) but not the cofactor pyrroloquinoline quinone (PQQ), which is essential for formation of the holoenzyme. Therefore, in the absence of exogenous PQQ, E. coli does not produce Gluconic Acid. Evidence is presented to show that the expression of an Erwinia herbicola gene in E. coli HB101(pMCG898) resulted in the production of Gluconic Acid, which, in turn, implied PQQ biosynthesis. Transposon mutagenesis showed that the essential gene or locus was within a 1.8-kb region of a 4.5-kb insert of the plasmid pMCG898. This 1.8-kb region contained only one apparent open reading frame. In this paper, we present the nucleotide sequence of this open reading frame, a 1,134-bp DNA fragment coding for a protein with an M(r) of 42,160. The deduced sequence of this protein had a high degree of homology with that of gene III (M(r), 43,600) of a PQQ synthase gene complex from Acinetobacter calcoaceticus previously identified by Goosen et al. (J. Bacteriol. 171:447-455, 1989). In minicell analysis, pMCG898 encoded a protein with an M(r) of 41,000. These data indicate that E. coli HB101(pMCG898) produced the GDH-PQQ holoenzyme, which, in turn, catalyzed the oxidation of glucose to Gluconic Acid in the periplasmic space. As a result of the Gluconic Acid production, E. coli HB101(pMCG898) showed an enhanced mineral phosphate-solubilizing phenotype due to Acid dissolution of the hydroxyapatite substrate.
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cloning of an erwinia herbicola gene necessary for Gluconic Acid production and enhanced mineral phosphate solubilization in escherichia coli hb101 nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone
Journal of Bacteriology, 1992Co-Authors: Shihtung Liu, Lanying Lee, Chinying Tai, Chienhui Hung, Yusun Chang, J H Wolfram, R Rogers, A H GoldsteinAbstract:Escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (GDH) but not the cofactor pyrroloquinoline quinone (PQQ), which is essential for formation of the holoenzyme. Therefore, in the absence of exogenous PQQ, E. coli does not produce Gluconic Acid. Evidence is presented to show that the expression of an Erwinia herbicola gene in E. coli HB101(pMCG898) resulted in the production of Gluconic Acid, which, in turn, implied PQQ biosynthesis. Transposon mutagenesis showed that the essential gene or locus was within a 1.8-kb region of a 4.5-kb insert of the plasmid pMCG898. This 1.8-kb region contained only one apparent open reading frame. In this paper, we present the nucleotide sequence of this open reading frame, a 1,134-bp DNA fragment coding for a protein with an M(r) of 42,160. The deduced sequence of this protein had a high degree of homology with that of gene III (M(r), 43,600) of a PQQ synthase gene complex from Acinetobacter calcoaceticus previously identified by Goosen et al. (J. Bacteriol. 171:447-455, 1989). In minicell analysis, pMCG898 encoded a protein with an M(r) of 41,000. These data indicate that E. coli HB101(pMCG898) produced the GDH-PQQ holoenzyme, which, in turn, catalyzed the oxidation of glucose to Gluconic Acid in the periplasmic space. As a result of the Gluconic Acid production, E. coli HB101(pMCG898) showed an enhanced mineral phosphate-solubilizing phenotype due to Acid dissolution of the hydroxyapatite substrate. Images
Hermann Sahm - One of the best experts on this subject based on the ideXlab platform.
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high yield 5 keto d Gluconic Acid formation is mediated by soluble and membrane bound gluconate 5 dehydrogenases of gluconobacter oxydans
Applied Microbiology and Biotechnology, 2006Co-Authors: Marcel Merfort, Ute Herrmann, Stephanie Bringermeyer, Hermann SahmAbstract:Gluconobacter oxydans DSM 2343 is known to catalyze the oxidation of glucose to Gluconic Acid, and subsequently, to 2-keto-d-Gluconic Acid (2-KGA) and 5-keto-d-Gluconic Acid (5-KGA), by membrane-bound and soluble dehydrogenases. In G. oxydans MF1, in which the membrane-bound gluconate-2-dehydrogenase complex was inactivated, formation of the undesired 2-KGA was absent. This mutant strain uniquely accumulates high amounts of 5-KGA in the culture medium. To increase the production rate of 5-KGA, which can be converted to industrially important l-(+)-tartaric Acid, we equipped G. oxydans MF1 with plasmids allowing the overproduction of the soluble and the membrane-bound 5-KGA-forming enzyme. Whereas the overproduction of the soluble gluconate:NADP 5-oxidoreductase resulted in the accumulation of up to 200 mM 5-KGA, the detected 5-KGA accumulation was even higher when the gene coding for the membrane-bound gluconate-5-dehydrogenase was overexpressed (240 to 295 mM 5-KGA). These results provide a basis for designing a biotransformation process for the conversion of glucose to 5-KGA using the membrane-bound as well as the soluble enzyme system.
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modification of the membrane bound glucose oxidation system in gluconobacter oxydans significantly increases gluconate and 5 keto d Gluconic Acid accumulation
Biotechnology Journal, 2006Co-Authors: Marcel Merfort, Ute Herrmann, Stephanie Bringermeyer, Mustafa Elfari, Helmut Gorisch, Hermann SahmAbstract:Gluconobacter oxydans DSM 2343 (ATCC 621H)catalyzes the oxidation of glucose to Gluconic Acid and subsequently to 5-keto-D-Gluconic Acid (5-KGA), a precursor of the industrially important L-(+)-tartaric Acid. To further increase 5-KGA production in G. oxydans, the mutant strain MF1 was used. In this strain the membrane-bound gluconate-2-dehydrogenase activity, responsible for formation of the undesired by-product 2-keto-D-Gluconic Acid, is disrupted. Therefore, high amounts of 5-KGA accumulate in the culture medium. G. oxydans MF1 was equipped with plasmids allowing the overexpression of the membrane-bound enzymes involved in 5-KGA formation. Overexpression was confirmed on the transcript and enzymatic level. Furthermore, the resulting strains overproducing the membrane-bound glucose dehydrogenase showed an increased Gluconic Acid formation, whereas the overproduction of gluconate-5-dehydrogenase resulted in an increase in 5-KGA of up to 230 mM. Therefore, these newly developed recombinant strains provide a basis for further improving the biotransformation process for 5-KGA production.
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A Gluconobacter oxydans mutant converting glucose almost quantitatively to 5-keto-d-Gluconic Acid
Applied Microbiology and Biotechnology, 2005Co-Authors: Mustafa Elfari, Ute Herrmann, Marcel Merfort, Hermann Sahm, Christoph Bremus, Viola Khodaverdi, Helmut GorischAbstract:Gluconobacter oxydans converts glucose to Gluconic Acid and subsequently to 2-keto- d -Gluconic Acid (2-KGA) and 5-keto- d -Gluconic Acid (5-KGA) by membrane-bound periplasmic pyrroloquinoline quinone-dependent and flavin-dependent dehydrogenases. The product pattern obtained with several strains differed significantly. To increase the production of 5-KGA, which can be converted to industrially important l -(+)-tartaric Acid, growth parameters were optimized. Whereas resting cells of G. oxydans ATCC 621H converted about 11% of the available glucose to 2-KGA and 6% to 5-KGA, with growing cells and improved growth under defined conditions (pH 5, 10% pO_2, 0.05% pCO_2) a conversion yield of about 45% 5-KGA from the available glucose was achieved. As the accumulation of the by-product 2-KGA is highly disadvantageous for an industrial application of G. oxydans , a mutant was generated in which the membrane-bound gluconate-2-dehydrogenase complex was inactivated. This mutant, MF1, grew in a similar way to the wild type, but formation of the undesired 2-KGA was not observed. Under improved growth conditions, mutant MF1 converted the available glucose almost completely (84%) into 5-KGA. Therefore, this newly developed recombinant strain is suitable for the industrial production of 5-KGA.
Chienhui Hung - One of the best experts on this subject based on the ideXlab platform.
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cloning of an erwinia herbicola gene necessary for Gluconic Acid production and enhanced mineral phosphate solubilization in escherichia coli hb101 nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone
Journal of Bacteriology, 1992Co-Authors: Shihtung Liu, Lanying Lee, Chinying Tai, Chienhui Hung, Yusun Chang, J H Wolfram, R Rogers, A H GoldsteinAbstract:Escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (GDH) but not the cofactor pyrroloquinoline quinone (PQQ), which is essential for formation of the holoenzyme. Therefore, in the absence of exogenous PQQ, E. coli does not produce Gluconic Acid. Evidence is presented to show that the expression of an Erwinia herbicola gene in E. coli HB101(pMCG898) resulted in the production of Gluconic Acid, which, in turn, implied PQQ biosynthesis. Transposon mutagenesis showed that the essential gene or locus was within a 1.8-kb region of a 4.5-kb insert of the plasmid pMCG898. This 1.8-kb region contained only one apparent open reading frame. In this paper, we present the nucleotide sequence of this open reading frame, a 1,134-bp DNA fragment coding for a protein with an M(r) of 42,160. The deduced sequence of this protein had a high degree of homology with that of gene III (M(r), 43,600) of a PQQ synthase gene complex from Acinetobacter calcoaceticus previously identified by Goosen et al. (J. Bacteriol. 171:447-455, 1989). In minicell analysis, pMCG898 encoded a protein with an M(r) of 41,000. These data indicate that E. coli HB101(pMCG898) produced the GDH-PQQ holoenzyme, which, in turn, catalyzed the oxidation of glucose to Gluconic Acid in the periplasmic space. As a result of the Gluconic Acid production, E. coli HB101(pMCG898) showed an enhanced mineral phosphate-solubilizing phenotype due to Acid dissolution of the hydroxyapatite substrate.
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cloning of an erwinia herbicola gene necessary for Gluconic Acid production and enhanced mineral phosphate solubilization in escherichia coli hb101 nucleotide sequence and probable involvement in biosynthesis of the coenzyme pyrroloquinoline quinone
Journal of Bacteriology, 1992Co-Authors: Shihtung Liu, Lanying Lee, Chinying Tai, Chienhui Hung, Yusun Chang, J H Wolfram, R Rogers, A H GoldsteinAbstract:Escherichia coli is capable of synthesizing the apo-glucose dehydrogenase enzyme (GDH) but not the cofactor pyrroloquinoline quinone (PQQ), which is essential for formation of the holoenzyme. Therefore, in the absence of exogenous PQQ, E. coli does not produce Gluconic Acid. Evidence is presented to show that the expression of an Erwinia herbicola gene in E. coli HB101(pMCG898) resulted in the production of Gluconic Acid, which, in turn, implied PQQ biosynthesis. Transposon mutagenesis showed that the essential gene or locus was within a 1.8-kb region of a 4.5-kb insert of the plasmid pMCG898. This 1.8-kb region contained only one apparent open reading frame. In this paper, we present the nucleotide sequence of this open reading frame, a 1,134-bp DNA fragment coding for a protein with an M(r) of 42,160. The deduced sequence of this protein had a high degree of homology with that of gene III (M(r), 43,600) of a PQQ synthase gene complex from Acinetobacter calcoaceticus previously identified by Goosen et al. (J. Bacteriol. 171:447-455, 1989). In minicell analysis, pMCG898 encoded a protein with an M(r) of 41,000. These data indicate that E. coli HB101(pMCG898) produced the GDH-PQQ holoenzyme, which, in turn, catalyzed the oxidation of glucose to Gluconic Acid in the periplasmic space. As a result of the Gluconic Acid production, E. coli HB101(pMCG898) showed an enhanced mineral phosphate-solubilizing phenotype due to Acid dissolution of the hydroxyapatite substrate. Images