APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2016
·Vol. 181
·期 4
·1347-1359
·
IF 1.606
Dai Yong,Huan Bin,Zhang Hai-Sheng,He Yu-Cai
To increase the biocatalytic activity of Escherichia coli CCZU-T15 whole cells, choline chloride/glycerol ([ChCl][Gly]) was firstly used as biocompatible solvent for the effective biotransformation of ethyl 4-chloro-3-oxobutanoate (COBE) into ethyl ( S )-4-chloro-3-hydroxybutanoate [( S )-CHBE]. Furthermore, L-glutamine (150 mM) was added into [ChCl][Gly]–water ([ChCl][Gly] 12.5 vol%, pH 6.5) media instead of NAD + for increasing the biocatalytic efficiency. To further improve the biosynthesis of ( S )-CHBE (>99 % e.e. ) by E. coli CCZU-T15 whole cells, Tween-80 (7.5 mM) was also added into this reaction media, and ( S )-CHBE (>9 % e.e. ) could be effectively synthesized from 2000 and 3000 mM COBE in the yields of 100 and 93.0 % by whole cells of recombinant E. coli CCZU-T15, respectively. TEM image indicated that the cell membrane was permeabilized and lost its integrity and when the cell was exposed to [ChCl][Gly]–water media with Tween-80. Clearly, this bioprocess has high potential for the effective biosynthesis of ( S )-CHBE (>99 % e.e. ).
研究领域:
生物化学
·
合成生物学
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产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2016
·
IF 4.917
Yu-Cai He,Zhi-Cheng Tao,Jun-Hua Di,Liang Chen,Lin-Bing Zhang,Dan-Ping Zhang,Gang-Gang Chong,Feng Liu,Yun Ding,Chun-Xia Jiang,Cui-Luan Ma
It was the first report that the concentrated hydrolyzates from the enzymatic hydrolysis of dilute NaOH (3 wt%)-soaking rice straw at 30 °C was used to form [Bmim]PF 6 -hydrolyzate (50:50, v/v) media for bioconverting ethyl 4-chloro-3-oxobutanoate (COBE) into ethyl ( R )-4-chloro-3-hydroxybutanoate [( R )-CHBE] (>99% e.e. ) with recombinant E. coli CCZU-A13. Compared with pure glucose, the hydrolyzates could promote both initial reaction rate and the intracellular NADH content. Furthermore, emulsifier OP-10 (20 mM) was employed to improve the reductase activity. Moreover, Hp-β-cyclodextrin (0.01 mol Hp-β-cyclodextrin/mol COBE) was also added into this bioreaction system for enhancing the biosynthesis of ( R )-CHBE from COBE by E. coli CCZU-A13 whole-cells. The yield of ( R )-CHBE (>99% e.e. ) from 800 mM COBE was obtained at 100% in the [Bmim]PF 6 -hydrolyzate (50:50, v/v) media by supplementation of OP-10 (20 mM) and Hp-β-CD (8 mM). In conclusion, an effective strategy for the biosynthesis of ( R )-CHBE was successfully demonstrated.
研究领域:
生物化学
·
微生物学
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DOI
高影响因子
ORGANIC PROCESS RESEARCH & DEVELOPMENT
·
2020
·
IF 3.023
Zeyu Yang,Wenjie Ye,Youyu Xie,Qinghai Liu,Rong Chen,Hualei Wang,Dongzhi Wei
Bioreductions catalyzed by alcohol dehydrogenases (ADHs) play an important role in the synthesis of chiral alcohols. However, the synthesis of ethyl (S)-4-chloro-3-hydroxybutyrate [(S)-CHBE], an important drug intermediate, has significant challenges concerning high substrate or product inhibition toward ADHs, which complicates its production. Herein, we evaluated a novel ADH, SmADH31, obtained from the Stenotrophomonas maltophilia genome, which can tolerate extremely high concentrations (6 M) of both substrate and product. The coexpression of SmADH31 and glucose dehydrogenase from Bacillus subtilis in Escherichia coli meant that as much as 660 g L–1 (4.0 M) ethyl 4-chloroacetoacetate was completely converted into (S)-CHBE in a monophasic aqueous system with a >99.9% ee value and a high space-time yield (2664 g L–1 d–1). Molecular dynamics simulation shed light on the high activity and stereoselectivity of SmADH31. Moreover, five other optically pure chiral alcohols were synthesized at high concentrations (100–462 g L–1) as a result of the broad substrate spectrum of SmADH31. All these compounds act as important drug intermediates, demonstrating the industrial potential of SmADH31-mediated bioreductions.
研究领域:
生物化学
·
药物化学
·
酶工程
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DOI
高影响因子
Journal of Materiomics
·
2021
·
IF 6.425
Hui Zhou,Jian Han,Xingyu Pu,Xuanhua Li
Sb 2 S 3 is a promising photovoltaic absorber with appropriate bandgap, excellent light absorption coefficient and great stability. However, the power conversion efficiency (PCE) of Sb 2 S 3 planar thin film solar cells is unsatisfactory for further commercial application due to low crystallinity and high resistivity of Sb 2 S 3 film. Here, we introduce an additive of 4-Chloro-3-nitrobenzenesulfonyl Chloride (CSCl) to alleviate these problems. The CSCl molecular contains two terminal Cl with lone pair electrons, which have the interaction with Sb atoms. Thus, the Sb 2 S 3 film with enhanced crystallization and low trap states has been obtained and the resistivity is also decreased. Furthermore, CSCl additive raises the Fermi level of the Sb 2 S 3 film, thereby enhancing the transport of electron from Sb 2 S 3 to TiO 2 . Consequently, the optimal PCE of Sb 2 S 3 solar cells is raised from 4.20% (control device) to 5.84%. Our research demonstrates a novel additive to enhance the photoelectric performance of Sb 2 S 3 solar cells.
研究领域:
材料科学
·
太阳能电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2010
·
IF 4.144
Lejin Xu,Jianlong Wang
The removal of biocide 4-chloro-3-methyl phenol (CMP) was investigated by heterogeneous Fenton-like system using nanoparticulate zero-valent iron (nZVI) as catalyst. The properties of nZVI before and after reaction were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effects of pH value, initial concentration of CMP, nZVI dose and hydrogen peroxide (H 2 O 2 ) concentration were determined. The experimental results showed that lower pH value and CMP concentration brought faster degradation rate. With the initial pH value of 6.1 and initial CMP concentration of 0.7 mM, the optimal dosage of reagents were 0.5 g nZVI/L and 3.0 mM H 2 O 2 . At pH 6.1, the degradation of CMP followed two-stage first-order kinetic that composed of an induction period (first-stage) and a followed rapid degradation stage (second-stage). According to the effects of scavengers n -butanol and KI, hydroxyl radicals ( OH), especially the surface-bounded •OH, had a dominant role in the oxidation of CMP. The degradation intermediates, carboxylic acids and chloride ion produced during the reaction process were monitored by high performance liquid chromatography (HPLC), liquid chromatography/mass spectrometry (LC/MS) and ion chromatography (IC). On the basis of these findings, the possible mechanistic steps of CMP degradation were proposed.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2009
·
IF 3.054
Shuang Song,Zhiwu Liu,Zhiqiao He,Yu Li,Jianmeng Chen,Chaolin Li
Biocides usually persist during municipal sewage treatment and are subsequently distributed into aquatic environments. To explore the capability of advanced oxidation processes for the rapid removal of biocides, we examined the total organic carbon (TOC) reduction of 4-chloro-3,5-dimethylphenol (PCMX) with a combination of UV/O 3 . Moreover, the related important parameters, including the mass transfer coefficient and light utilization efficiency, in PCMX degradation were determined. The UV/O 3 experimental results showed a pronounced synergistic effect, leading to the nearly complete elimination of TOC within 75 min. Thus, the effect of operating variables was investigated as a function of pH, ozone dosage, bulk temperature and the initial concentration of PCMX. The efficiency of PCMX mineralization increased with an increase in ozone dose up to 3.1 g h −1 , and a decrease in the initial concentration from 250 to 100 mg L −1 . The optimal pH value was 4.0, and the preferred bulk temperature was 20 °C on the basis of the influence of temperature on reaction rate and ozone solubility. The major aromatic intermediates identified by gas chromatography/mass spectrometry were 2,6-dimethylbenzene-1,4-diol, 2,6-dimethylbenzo-1,4-quinone, 2,6-bis(hydroxymethyl)benzo-1,4-quinone, and 2,6-dimethylbenzo-1,4-aldehyde. Quantitative determination of related carboxylic acid and inorganic anions was done by ion chromatography . On the basis of the identified reaction products, a possible degradation pathway for the UV/O 3 oxidation of PCMX in aqueous media is proposed.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF BIOTECHNOLOGY
·
2015
·
IF 2.871
Yu-Cai He,Zhi-Cheng Tao,Yun Ding,Dan-Ping Zhang,Yin-Qin Wu,Yun Lu,Feng Liu,Yu-Feng Xue,Cheng Wang,Jian-He Xu
To avoid adding NAD + and effectively transform ethyl 4-chloro-3-oxobutanoate, the mixture of l -glutamine (200 mM) and d -xylose (250 mM) was added into in n -butyl acetate–water (10:90, v/v) biphasic system instead of NAD + for increasing the biocatalytic efficiency. To further improve the synthesis of optically pure ethyl ( R )-4-chloro-3-hydroxybutanoate (>99% ee ), β-cyclodextrin was also added into this reaction media, and ethyl ( R )-4-chloro-3-hydroxybutanoate (>99% ee ) could be effectively synthesized from 800 mM ethyl 4-chloro-3-oxobutanoate in the yield of 100% by whole-cells of recombinant E. coli CCZU-A13. Finally, the possible mechanism for improving the reductase activity by supplementation of l -glutamine, d -xylose and β-CD was proposed. In conclusion, this strategy has high potential for the effective biosynthesis of ethyl ( R )-4-chloro-3-hydroxybutanoate (>99% ee ).
研究领域:
生物化学
·
酶工程
·
合成生物学
✓ 已验证
DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 2.467
Qin Xu,Wei-Yi Tao,He Huang,Shuang Li
An NADPH-dependent carbonyl reductase (YlCR2) from Yarrowia lipolytica was discovered by genome mining, overexpressed in Escherichia coli BL21 and purified to homogeneity. To efficiently synthesize ethyl ( S )-4-chloro-3-hydroxybutanoate (( S )-CHBE) (99%, e.e), the highly stereoselective bioreduction of ethyl 4-chloro-3-oxobutanoate (COBE) into ( S )-CHBE with the recombinant E. coli BL21/pETYlCR2 was successfully demonstrated in an n -butyl acetate-water biphasic system (1:1, v/v) with NADPH self-regeneration by substrate-coupled system using sorbitol or mannitol as co-substrate. The optimum reaction condition for the biotransformation of COBE in the biphasic system were 3000 mM COBE, (1.2 or 1.3 mmol/mmol COBE) mannitol or sorbitol, 0.2 mM or 0.4 mM NADP + , 0.12 or 0.14 g (wet weight)/ml cell dosage, pH 5.0, 30 °C; ( S )-CHBE with yield of 90% and e.e of 99% was obtained after 10 h reaction. Furthermore, 3000 mM COBE could also be completely biotransformed after 20 h without addition of expensive cofactor NADP + . Significantly, E. coli BL21/pETYlCR2 shows the high potential in the industrial production of ( S )-CHBE.
研究领域:
生物化学
·
合成生物学
·
酶工程
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Xuecai Wei,Xiaoyang Yue,Quan Yuan,Ying He,Li Ma,Liya Zhou,Guanhua Liu,Yunting Liu,Yanjun Jiang
Ethyl ( S )-4‑chloro-3-hydroxybutyrate [( S )-CHBE] is attractive as a necessary intermediate for the production of highly valued products in pharmaceutical industries. Nowadays, alcohol dehydrogenases play an increasingly essential role in the asymmetric synthesis of chiral alcohols. In this work, a nicotinamide adenine dinucleotide (NADH)-dependent alcohol dehydrogenase from Pseudomonas bacterium ( Pb ADH) was obtained by genome mining method and identified to exhibit an excellent tolerance against the high substrate and product concentrations. For the regeneration of NADH, Bacillus megaterium glucose dehydrogenase ( Bm GDH) was successfully co-expressed with Pb ADH in E. coli cells. So much as 3.5 M (574 g/L) ethyl 4-chloroacetoacetate (COBE) can be converted to ( S )-CHBE completely with a > 99 % ee value under the catalysis by recombinant cells, even in a monophasic aqueous media with a single batch charge of substrate. In addition, in order to verify the substrate scope of Pb ADH, six other α/β-ketone esters and aromatic ketones were also evaluated as substrates at high substrate concentrations (100–650 g/L), and the corresponding chiral alcohols with highly optical purity were also achieved by co-expressed E. coli cells.
研究领域:
生物化学
·
酶工程
·
制药工业
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产品关联
DOI
高影响因子
Bioresource Technology Reports
·
2018
·
IF 0
Bing-Qian Wang,Bo Peng,Jian-Fei Sun,Chu Wang,Ke Jiang,Jing-Hao Ma,Peng-Qi Zhang,Yu-Cai He
An effecti v e combination pretreatment of bamboo shoot shell (BSS) using Emulsifier OP-10 (0.5%, w/v) in the acidified media (pH 4.0) by autoclaving (120 °C, 40 min) was conducted. After BSS slurry without detoxification was enzymatically hydrolyzed for 96 h, glucose (25.2 g/L) and xylose (7.5 g/L) were obtained from 50 g/L BSS at high yields. HPLC results showed that no potential inhibitors (furfural and 5-hydroxymethylfurfural) formed. In the hydrolysates , an effective biocatalytic synthesis of ethyl ( S )-4-chloro-3-hydroxybutanoate (100% yield; >99% e.e. ) from 1000 mM ethyl 4-chloro-3-oxobutanoate was developed without the extra addition of cofactors within 24 h. In summary, this combination strategy involving biomass pretreatment, enzymatic saccharification , and bioreduction can be developed for producing chiral alcohols.
研究领域:
生物质预处理
·
酶解糖化
·
生物催化
·
手性醇合成
✓ 已验证
DOI
PROCESS BIOCHEMISTRY
·
2020
·
IF 2.952
Yuan Lu,Hongqian Dai,Hanbing Shi,Lan Tang,Xingyuan Sun,Zhimin Ou
Fe 3 O 4 -Arg was selected as the optimal carrier due to its high activity recovery of immobilized cells in the preparation of Fe 3 O 4 -Arg-Cells. The optimal immobilization conditions for the preparation of Fe 3 O 4 -Arg-Cells were 30 °C, 4 h, pH 7, and 3 g dry yeast. The activity recovery of immobilized cells reached 76.8 %. For a batch reduction in a shaker in an alternating magnetic field, Fe 3 O 4 -Arg-Cells were used as a catalyst to gain ethyl ( R )-4-chloro-3-hydroxybutyrate (( R )-CHBE). For further improvement in reduction productivity, a continuous reduction in the magnetic fluidized bed reactor system (MFBRS) was completed. Under their optimal transformation conditions, it took 24 h for Fe 3 O 4 -Arg-Cells to complete the conversion of ethyl 4-chloro-3-oxobutanoate (COBE) (0.8553 mol/L) in the shaker and only 8 h for the batch reduction in an alternating magnetic field. Continuous reduction in MFBRS provided new ideas for the efficient production of ( R )-CHBE; 1.5882 mol/L (10 mL) of COBE can be completely converted in 6 h. The conversion and enantiomeric excess (e.e.) of ( R )-CHBE were 100 % and above 99.9 % respectively, in the three reaction systems mentioned above.
研究领域:
生物化学
·
合成生物学
·
纳米技术
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2015
·
IF 4.494
Yu-Cai He,Dan-Ping Zhang,Zhi-Cheng Tao,Yun Lu,Yun Ding,Feng Liu,Zheng-Zhong Zhu,Huan Rui,Gao-Wei Zheng,Xian Zhang
To reduce dependence on the expensive cofactor and effectively biotransform ethyl 4-chloro-3-oxobutanoate, l -glutamine and glycine were found to enhance the content of intracellular NADH and the reductase activity. Adding the mixture of 200 mM of l -glutamine and 500 mM of glycine to the reaction media, a 1.67-fold of reductase activity was increased over the control without the addition of the two compounds. Moreover, β-cyclodextrin (0.4 mol β-cyclodextrin/mol ethyl 4-chloro-3-oxobutanoate) was also added into this reaction media, and the biocatalytic activity of the whole-cell biocatalyst of Escherichia coli CCZU-K14 was increased by 1.34-fold than that without β-cyclodextrin. In this β-cyclodextrin–water media containing l -glutamine (200 mM) plus glycine (500 mM), ethyl ( S )-4-chloro-3-hydroxybutanoate (>99% ee ) could be obtained from 3000 mM ethyl 4-chloro-3-oxobutanoate in the yield of 98.0% after 8 h. All the positive features demonstrate the potential applicability of the bioprocess for the large-scale production of ethyl ( S )-4-chloro-3-hydroxybutanoate.
研究领域:
生物化学
·
酶工程
·
有机合成
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）