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Xinggui Zhou - One of the best experts on this subject based on the ideXlab platform.
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retraction of determination of ternary vapor liquid equilibrium of dimethyl oxalate methanol 1 2 Butanediol under atmosphere pressure
Journal of Chemical & Engineering Data, 2020Co-Authors: Rongchun Shen, Yun Chen, Yunhai Shi, Jinghong Zhou, Xinggui ZhouAbstract:Isobaric vapor–liquid equilibrium (VLE) data for the dimethyl oxalate + methanol and methanol + 1,2-Butanediol binary systems, as well as the VLE for the dimethyl oxalate + methanol + 1,2-butanedio...
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determination of ternary vapor liquid equilibrium of dimethyl oxalate methanol 1 2 Butanediol under atmosphere pressure
Journal of Chemical & Engineering Data, 2019Co-Authors: Rongchun Shen, Yun Chen, Yunhai Shi, Jinghong Zhou, Xinggui ZhouAbstract:Isobaric vapor–liquid equilibrium (VLE) data for the dimethyl oxalate + methanol and methanol + 1,2-Butanediol binary systems, as well as the VLE for the dimethyl oxalate + methanol + 1,2-butanedio...
Xiangxian Ying - One of the best experts on this subject based on the ideXlab platform.
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characterization of a 2r 3r 2 3 Butanediol dehydrogenase from rhodococcus erythropolis wz010
Molecules, 2015Co-Authors: Meijuan Huang, Qingqing Song, Jianzhong Shao, Xiangxian YingAbstract:The gene encoding a (2R,3R)-2,3-Butanediol dehydrogenase from Rhodococcus erythropolis WZ010 (ReBDH) was over-expressed in Escherichia coli and the resulting recombinant ReBDH was successfully purified by Ni-affinity chromatography. The purified ReBDH in the native form was found to exist as a monomer with a calculated subunit size of 37180, belonging to the family of the zinc-containing alcohol dehydrogenases. The enzyme was NAD(H)-specific and its optimal activity for acetoin reduction was observed at pH 6.5 and 55 °C. The optimal pH and temperature for 2,3-Butanediol oxidation were pH 10 and 45 °C, respectively. The enzyme activity was inhibited by ethylenediaminetetraacetic acid (EDTA) or metal ions Al3+, Zn2+, Fe2+, Cu2+ and Ag+, while the addition of 10% (v/v) dimethyl sulfoxide (DMSO) in the reaction mixture increased the activity by 161.2%. Kinetic parameters of the enzyme showed lower Km values and higher catalytic efficiency for diacetyl and NADH in comparison to those for (2R,3R)-2,3-Butanediol and NAD+. The activity of acetoin reduction was 7.7 times higher than that of (2R,3R)-2,3-Butanediol oxidation when ReBDH was assayed at pH 7.0, suggesting that ReBDH-catalyzed reaction in vivo might favor (2R,3R)-2,3-Butanediol formation rather than (2R,3R)-2,3-Butanediol oxidation. The enzyme displayed absolute stereospecificity in the reduction of diacetyl to (2R,3R)-2,3-Butanediol via (R)-acetoin, demonstrating its potential application on the synthesis of (R)-chiral alcohols.
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characterization of a stereospecific acetoin diacetyl reductase from rhodococcus erythropolis wz010 and its application for the synthesis of 2s 3s 2 3 Butanediol
Applied Microbiology and Biotechnology, 2014Co-Authors: Zhao Wang, Qingqing Song, Yifang Wang, Bin Xiong, Yinjun Zhang, Jianyong Zheng, Xiangxian YingAbstract:Rhodococcus erythropolis WZ010 was capable of producing optically pure (2S,3S)-2,3-Butanediol in alcoholic fermentation. The gene encoding an acetoin(diacetyl) reductase from R. erythropolis WZ010 (ReADR) was cloned, overexpressed in Escherichia coli, and subsequently purified by Ni-affinity chromatography. ReADR in the native form appeared to be a homodimer with a calculated subunit size of 26,864, belonging to the family of the short-chain dehydrogenase/reductases. The enzyme accepted a broad range of substrates including aliphatic and aryl alcohols, aldehydes, and ketones. It exhibited remarkable tolerance to dimethyl sulfoxide (DMSO) and retained 53.6 % of the initial activity after 4 h incubation with 30 % (v/v) DMSO. The enzyme displayed absolute stereospecificity in the reduction of diacetyl to (2S,3S)-2,3-Butanediol via (S)-acetoin. The optimal pH and temperature for diacetyl reduction were pH 7.0 and 30 °C, whereas those for (2S,3S)-2,3-Butanediol oxidation were pH 9.5 and 25 °C. Under the optimized conditions, the activity of diacetyl reduction was 11.9-fold higher than that of (2S,3S)-2,3-Butanediol oxidation. Kinetic parameters of the enzyme showed lower K m values and higher catalytic efficiency for diacetyl and NADH in comparison to those for (2S,3S)-2,3-Butanediol and NAD+, suggesting its physiological role in favor of (2S,3S)-2,3-Butanediol formation. Interestingly, the enzyme showed higher catalytic efficiency for (S)-1-phenylethanol oxidation than that for acetophenone reduction. ReADR-catalyzed asymmetric reduction of diacetyl was coupled with stereoselective oxidation of 1-phenylethanol, which simultaneously formed both (2S,3S)-2,3-Butanediol and (R)-1-phenylethanol in great conversions and enantiomeric excess values.
Liaoyuan Zhang - One of the best experts on this subject based on the ideXlab platform.
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an artificial synthetic pathway for acetoin 2 3 Butanediol and 2 butanol production from ethanol using cell free multi enzyme catalysis
Green Chemistry, 2018Co-Authors: Liaoyuan Zhang, Raushan Kumar Singh, Dakshinamurthy Sivakumar, Zewang Guo, Fanbing Chen, Xiong Guan, Yun Chan Kang, Jungkul LeeAbstract:Upgrading ethanol to higher order alcohols is desired but difficult using current biotechnological methods. In this study, we designed a completely artificial reaction pathway for upgrading ethanol to acetoin, 2,3-Butanediol, and 2-butanol in a cell-free bio-system composed of ethanol dehydrogenase, formolase, 2,3-Butanediol dehydrogenase, diol dehydratase, and NADH oxidase. Under optimized conditions, acetoin, 2,3-Butanediol, and 2-butanol were produced at 88.78%, 88.28%, and 27.25% of the theoretical yield from 100 mM ethanol, respectively. These results demonstrate that this artificial synthetic pathway is an environmentally-friendly novel approach for upgrading bio-ethanol to acetoin, 2,3-Butanediol, and 2-butanol.
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Efficient (3S)-Acetoin and (2S,3S)-2,3-Butanediol Production from meso-2,3-Butanediol Using Whole-Cell Biocatalysis
MDPI AG, 2018Co-Authors: Feixue Chen, Zewang Guo, Meijing Sun, Huifang Gao, Hui Lin, Jiebo Chen, Wensong Jin, Yunlong Yang, Liaoyuan ZhangAbstract:(3S)-Acetoin and (2S,3S)-2,3-Butanediol are important platform chemicals widely applied in the asymmetric synthesis of valuable chiral chemicals. However, their production by fermentative methods is difficult to perform. This study aimed to develop a whole-cell biocatalysis strategy for the production of (3S)-acetoin and (2S,3S)-2,3-Butanediol from meso-2,3-Butanediol. First, E. coli co-expressing (2R,3R)-2,3-Butanediol dehydrogenase, NADH oxidase and Vitreoscilla hemoglobin was developed for (3S)-acetoin production from meso-2,3-Butanediol. Maximum (3S)-acetoin concentration of 72.38 g/L with the stereoisomeric purity of 94.65% was achieved at 24 h under optimal conditions. Subsequently, we developed another biocatalyst co-expressing (2S,3S)-2,3-Butanediol dehydrogenase and formate dehydrogenase for (2S,3S)-2,3-Butanediol production from (3S)-acetoin. Synchronous catalysis together with two biocatalysts afforded 38.41 g/L of (2S,3S)-Butanediol with stereoisomeric purity of 98.03% from 40 g/L meso-2,3-Butanediol. These results exhibited the potential for (3S)-acetoin and (2S,3S)-Butanediol production from meso-2,3-Butanediol as a substrate via whole-cell biocatalysis
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a new nad h dependent meso 2 3 Butanediol dehydrogenase from an industrially potential strain serratia marcescens h30
Applied Microbiology and Biotechnology, 2014Co-Authors: Liaoyuan Zhang, Xiong Guan, Quanming Xu, Senran Zhan, Yongyu Li, Kaihui Hu, Yaling ShenAbstract:The budC gene coding for a new meso-2,3-Butanediol dehydrogenase (BDH) from Serratia marcescens H30 was cloned and expressed in Escherichia coli BL21(DE3), purified, and characterized for its properties. The recombinant BDH with a molecular weight of 27.4 kDa exhibited a reversible transformation between acetoin and 2,3-Butanediol. In the presence of NADH, BDH could catalyze the reduction of diacetyl and (3R)-acetoin to (3S)-acetoin and meso-2,3-Butanediol, respectively, while (3S)-acetoin as a substrate could be further transformed into (2S, 3S)-2,3-Butanediol at pH 9.0. For diol oxidation reactions, (3R)-acetoin and (3S)-acetoin were obtained when meso-2,3-Butanediol and (2S,3S)-2,3-Butanediol were used as the substrates with BDH and NAD+. (2R,3R)-2,3-Butanediol was not a substrate for the BDH at all. The low Km value (4.1 mM) in meso-2,3-Butanediol oxidation reaction and no activity for diacetyl, acetoin, and 2,3-Butanediol as the substrates with NADP+/NADPH suggested that the budC gene product belongs to a NAD(H)-dependent meso-2,3-BDH. Maximum activities for diacetyl and (3S/3R)-acetoin reduction were observed at pH 8.0 and pH 5.0 while for meso-2,3-Butanediol oxidation it was pH 8.0. However, the optimum temperature for oxidation and reduction reactions was about 40 °C. In addition, the BDH activity for meso-2,3-Butanediol oxidation was enhanced in the presence of Fe2+ and for diacetyl and (3S/3R)-acetoin reduction in the presence of Mg2+ and Mn2+, while several metal ions inhibited its activity, particularly Fe3+ for reduction of diacetyl and acetoin. Sequence analysis showed that the BDH from S. marcescens H30 possessed two conserved sequences including the coenzyme binding motif (GxxxGxG) and the active-site motif (YxxxK), which are present in the short-chain dehydrogenase/reductase superfamily.
Rongchun Shen - One of the best experts on this subject based on the ideXlab platform.
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retraction of determination of ternary vapor liquid equilibrium of dimethyl oxalate methanol 1 2 Butanediol under atmosphere pressure
Journal of Chemical & Engineering Data, 2020Co-Authors: Rongchun Shen, Yun Chen, Yunhai Shi, Jinghong Zhou, Xinggui ZhouAbstract:Isobaric vapor–liquid equilibrium (VLE) data for the dimethyl oxalate + methanol and methanol + 1,2-Butanediol binary systems, as well as the VLE for the dimethyl oxalate + methanol + 1,2-butanedio...
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determination of ternary vapor liquid equilibrium of dimethyl oxalate methanol 1 2 Butanediol under atmosphere pressure
Journal of Chemical & Engineering Data, 2019Co-Authors: Rongchun Shen, Yun Chen, Yunhai Shi, Jinghong Zhou, Xinggui ZhouAbstract:Isobaric vapor–liquid equilibrium (VLE) data for the dimethyl oxalate + methanol and methanol + 1,2-Butanediol binary systems, as well as the VLE for the dimethyl oxalate + methanol + 1,2-butanedio...
An-ping Zeng - One of the best experts on this subject based on the ideXlab platform.
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production of 1 3 propanediol 2 3 Butanediol and ethanol by a newly isolated klebsiella oxytoca strain growing on biodiesel derived glycerol based media
Process Biochemistry, 2012Co-Authors: Maria Metsoviti, An-ping Zeng, Kleopatra Paraskevaidi, Apostolis A Koutinas, Seraphim PapanikolaouAbstract:Abstract The production of 1,3-propanediol, 2,3-Butanediol and ethanol was studied, during cultivations of strain Klebsiella oxytoca FMCC-197 on biodiesel-derived glycerol based media. Different kinds of glycerol feedstocks and experimental conditions had an important impact upon the distribution of metabolic products; production of 1,3-propanediol was positively influenced by stable pH conditions and by the absence of N 2 gas infusions throughout the fermentation. Thus, during batch bioreactor fermentations conducted at increasing glycerol concentrations, 1,3-propanediol at 41.3 g/L and yield ∼47% (w/w) was achieved at initial glycerol concentration ∼120 g/L. At even higher initial glycerol media (150 and 170 g/L), growth was not ceased, but 1,3-propanediol production declined. During fed-batch fermentation under optimal experimental conditions, 126 g/L of glycerol were converted into 50.1 g/L of 1,3-propanediol. In this experiment, also 25.2 g/L of ethanol (conversion yield ∼20%, w/w) were formed. A batch-bioreactor culture was performed under non-sterilized conditions and the 1,3-propanediol production was almost equivalent to the sterilized process. Concerning 2,3-Butanediol formation, the most detrimental parameter was the absence of N 2 sparging and as a result, no 2,3-Butanediol was produced. The presence of glucose as co-substrate seriously enhanced 2,3-Butanediol production; when commercial glucose was employed as sole substrate, 32.1 g/L of 2,3-Butanediol were formed.
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Novel (2R,3R)-2,3-Butanediol Dehydrogenase from Potential Industrial Strain Paenibacillus polymyxa ATCC 12321
Applied and environmental microbiology, 2011Co-Authors: Jibin Sun, Rajesh Reddy Bommareddy, Lifu Song, An-ping ZengAbstract:A (2R,3R)-2,3-Butanediol dehydrogenase (BDH99::67) from Paenibacillus polymyxa ATCC 12321 was functionally characterized. The genetic characteristics of BDH99::67 are completely different from those of meso- and (2S,3S)-2,3-Butanediol dehydrogenases. The results showed that BDH99::67 belongs to the medium-chain dehydrogenase/reductase superfamily and not to the short-chain dehydrogenase/reductase superfamily, to which meso- and (2S,3S)-2,3-Butanediol dehydrogenases belong.
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fermentation of glycerol to 1 3 propanediol and 2 3 Butanediol by klebsiella pneumoniae
Applied Microbiology and Biotechnology, 1998Co-Authors: Hanno Biebl, An-ping Zeng, K Menzel, W D DeckwerAbstract:Klebsiella pneumoniae was shown to convert glycerol to 1,3-propanediol, 2,3-Butanediol and ethanol under conditions of uncontrolled pH. Formation of 2,3-Butanediol starts with some hours' delay and is accompanied by a reuse of the acetate that was formed in the first period. The fermentation was demonstrated in the type strain of K. pneumoniae, but growth was better with the more acid-tolerant strain GT1, which was isolated from nature. In continuous cultures in which the pH was lowered stepwise from 7.3 to 5.4, 2,3-Butanediol formation started at pH 6.6 and reached a maximum yield at pH 5.5, whereas formation of acetate and ethanol declined in this pH range. 2,3-Butanediol and acetoin were also found among the products in chemostat cultures grown at pH 7 under conditions of glycerol excess but only with low yields. At any of the pH values tested, excess glycerol in the culture enhanced the Butanediol yield. Both effects are seen as a consequence of product inhibition, the undissociated acid being a stronger trigger than the less toxic diols and acid anions. The possibilities for using the fermentation type described to produce 1,3-propanediol and 2,3-Butanediol almost without by-products are discussed.
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use of respiratory quotient as a control parameter for optimum oxygen supply and scale up of 2 3 Butanediol production under microaerobic conditions
Biotechnology and Bioengineering, 1994Co-Authors: An-ping Zeng, T G Byun, Clemens Posten, W D DeckwerAbstract:The respiratory quotient (RQ) was found to be a suitable control parameter for optimum oxygen supply for the production of 2,3-Butanediol + acetoin under microaerobic conditions. In laboratory scale continuous cultures optimum production of 2,3-Butanediol + acetoin was obtained at an RQ value between 4.0 to 4.5. This agreed well with optimum RQ value (4.0) stoichiometrically derived from the bioreactions involved. In fed-batch cultures product concentrations as high as 102.9 g/L (96.0 g/L Butanediol + 6.9 g/L acetoin) can be achieved within 32 h cultivation with an RQ control algorithm for oxygen supply. Under similar conditions only 85.7 g/L product (77.6 g/L Butanediol + 8.1 g/L acetoin) was obtained with control of constant oxygen supply rate throughout the cultivation.In pilot scale batch cultures under identical oxygen supply rate the achievable RQ value was found to be strongly influenced by the reactor type and scale. The initial oxygen supply rate influenced the achievable RQ as well. However, in all the reactors studied the specific product formation rate of cells in the exponential growth phase was only a function of RQ. The same optimum RQ value as found in continuous cultures was obtained. It was thus concluded that RQ can be used as a control parameter for optimum production of 2,3-Butanediol + acetoin in both laboratory and pilot plant scale reactors.
